Preface: Wow, this got out of hand. Turned into a full-on rant with a hefty does of rambling. You've been warned.
If it had taken more cues from Final Fantasy 7 apart from incocsequential influences in setup and character design.
What do I mean by that? I'm not entirely sure myself but I think I mean to say they could have taken more beats and themes from other Final Fantasies. I mean, their opening hours is in a lot of ways similar with 7's:
We're introduced to our ex-military and Black gun-weilding character by way of train.
They fight a giant robot scorpion thing.
They're branded as terrorists by railing against the system.
The problem is in execution. The whole story takes place in medias res, which isn't a bad thing per se, but the way in which details are given and the 13 day story structure they provide are paced out so poorly that by the time we finally get around to revealing why and how each individual got to their part in the story, I either forgot the relevence of importance or long stopped caring about character motivations (as flimsy as some were).
I think not being able to really explore Cocoon or see any real signs of unrest or strife or corruption or disenfranchisement pretty much anything that strayed apart from the perfectly crafted hallyway jog to Grand Pulse really was a detriment to this game's ability to set up any semblance of story or atmosphere.
Let's look at 7 again, (yes, I'm going to make a lot of comparisons to 7 as I find it does atmosphere and setting better than most of the other games in the series). In the opening hours of the game, you're told who and your compatriots are, what they are doing, why they are doing it. Not only that, but you learn more subtle things such as character relationships and dynamics as well as hints of foreshadowing. But one of the most important things 7 does that 13 doesn't is that it leaves you alone and abandoned in the slums and lets you explore your surroundings. You can talk with the local denizens and just soak up the utter shit stain that is the lower sectors under the plates. This place is utterly broken and people have nothing but their vices and each other to keep themselves together.
13 tried to accomplish this in visual shorthand via their skyboxes of Cocoon, but apart from the robed folks getting shipped out of Cocoon, I never really saw anyone particularly down on their luck or disenfranchised. I never really much of anyone outside of cutscenes, and even then the random citezens all seemed to be living nice peaceful Stepford lives. Whether they're supposed to be a sort of Orwellian society where everyone is content with their lives and have no qualms about not questioning their governing body's word or not, I have no way of knowing. The story didn't care to mention it. Near as I could figure, Cocoon is meant to be a sort of paradise floating above the actual world upon all lesser beings and creatures are meant to be.
Another thing it could have learned from 7: Clear-cut goals and Progressively raising the stakes.
7 had you starting out with domestic terrorism to strike back at a mega-corporation. Over time, you get to a point where an ancient sentient space cancer is trying to crash a huge fuck-off meteor into the planet in order to harness all of the planet's life stream energies and essentially become a god (okay, I might have a few of the finer details wrong, but you get what I mean shit gets progressively more real).
13 had you traipsing around aimlessly (in the context of the narrative, let's be honest, you couln't wander aimlessly if tried to in 13) for the first few hours slowly spoon-feeding you tedious unskippable tutorials on things we've comprehended hours ago. I don't believe the game even trusted you with paradigm shifts up until the 6-8 hour mark where you get Fang added to your party. I shit a lot on Kingdom Hearts II's opening tutorial level, but more than 80% of XIII's entire game is tutorials and hand-holding. I'm really surprised now that when I bought my copy I wasn't also issued a Square-Enix representative to play the game for me. But I digress... You start out (seemingly for no discernable reason) on a train fighting soldiers and then you're looking for a girl named SERAH and then you see a nice lady die in front of her son and then you eventually meet a machine-god thing and then you're branded as something the game never really bothers to properly explain and then you have to escape Cocoon and then you eventually all collectively decide to kill the machine-god, but wait, isn't that what the machine-god wants, but let's kill it anyways (x infinity)...
There were no people to interact with, no shops, no towns to explore. What wasn't destroyed as a result of the party's actions looked fairly well kept, if not prestine. There really didn't seem to be signs of dissent or oppression apart from obviously shipping a bunch of people we don't know anything about off of Cocoon. So we really only have the group's words to go off of, which, let's be honest, really isn't a whole lot. A lot of their dialog is very cyclical, mainly arguing with each other if they should fulfill their focus or try to find another way. This keeps happening and it got me to the point where I had subtitles on and I was skimming the dialog to see if there was ANY sort of clear-cut goal I as the player or they as the group could get behind.
Another thing it could learn from pretty much any other entry in the Final Fantasy series is the way input matters to players. I understand what they were going for, I honestly do. They wanted to streamline combat to make it feel more frenetic and charged, and possibly to "appeal to a wider audience." But the main problem I have with what their vision of streamlined combat entailed is a distinct lack of control or meaningful input. Battles are a chore in 13, though I can't decide who's more resentful of combat: the player or the actual combat system. You see, none of the enemy units have visible displays of hit points, and you often need to stagger most basic and non-basic enemies to do any appreciable damage to them. So you would think the combat would show some similarities to X's combat system where every party member had an assigned role and was useful against certain enemy types. Nooooooooope~! After the game thinks you're not going to swallow you own tongue, 13 has any party member able to fulfill any role you want. The question is, why bother? At the point in the game where this option opens up to you, you're already accustomed to each individual performing certain roles and vastly superior to others. Sure, you can max out Vanille as a commando, but why would you? Lightning and Fang (and Snow I guess, honestly I avoided using him like the plague if I was able) are already your main damage dealers because up until that point, they've been locked into very specific roles to be utilized as such.
It makes me laugh when people try to criticize 12's combat system to try and defend 13's. "It plays itself." Yeah, only if you put in the time and effort it takes to learn and build upon the gambit system. Then it's awesome. You can literally go make a sandwich and leave the game running while in a dungeon, come back and see your party just grinded out a couple of levels. And I can understand why that still might be offputting or unappealing to many, but it's still involving, you still have to put in the time to make it work. Unlike 13, where you have no significant input apart from shifting jobs during combat or going against the auto-battle button, which would actively waste your time and extend the fight even longer with you manual inputs as auto-battle instantly chooses the best possible attacks for your current situation.
One other big problem with 13 is that there's no real main character. And if you say Lightning is the main character then you're wrong. Just because she is on the box of the game doesn't mean she's the main character. Would you honestly tell me with a straight face that Vaan is the main character in 12? No, the main character is Ashe and possibly Balthier if you want to get super technical. There is no one character in 13 for the player to latch onto. I can understand wanting to think and identify with Lightning as being the main character because she is the one we fare first introduced to and first control. That does not make her the main character. In fact, it's hard for me to determine who really could be the main character out of the 6. I know I'd like it to be Sahz mainly because when he's not being played up for laughs as "black people, am I right?" I identified more with a father's desire to see his son again more than any other character. That fact is, none of them have any real depth or character, so none of them could really be the main anchor point for a player like me to really invest myself with. At a certain point, I stopped referring to them by name and instead attached nick-names to them.
Lightning - Bitch
Sazh - Afroman
Hope - Whiney Bitch
Vanille - Kooky
Snow - Asshat/Idiot/Fuckwit/Dumbass/Frosty the Bro-man/Dullard
Fang - Aussie
No character ever at any point felt like a fully realized or (at the very least) developed character, and the flashbacks to earlier on in the week did nothing to really flesh themselves out. Lightning's is probably the best example. As my nickname for her suggests, she was a straight up bitch to her sister on her (Lightning's) birthday and an even bigger bitch to try and tell her sister how to live her life with who she could and couldn't marry. We're given some additional information as to why Lightning acts the way she does, but it comes off as more of a justification for herself rather than an actual explanation. For as much as 13 tries to present itself in a very cinematic way, it constantly either breaks or ignores the cardinal rule of visual storytelling: Show. Don't tell. Lightning's (and by extention, every other character we control) backstory and character could at least have been more convincing for me if we were actually shown an instance of her growing up with her family or if there was a scar (could be mental or physical, I'm not picky) from a domestic abuse situation that started the building blocks for the character we're shown at present. As it is in the game, I don't care about anything Bitch says because most people like Bitch often make excuses for themselves to justify their behavior.
Fuck, in 7 even Cait Sith's operator had a backstory, character, and motivations for continuing on with the party and you could choose to completely ignore him outside of a few combat instances.
So I guess the main complaint I have is that there's nothing to really latch onto for me in this game.
The story is a very stock premise that I've seen done in countless other games and anime, and much better in my opinion. There's nothing in the game that I found particularly interesting. The world-building was nothing if you only relied on the game itself, but there's actually a shit ton of background information for the world of Cocoon and Pulse hidden in a menu tab for the analects. I didn't bother mentioning it because the game didn't either. Again, show. Don't tell.
The combat is uninteresting, feels resentful to have the player be involved at all, and if staggering weren't a core mechanic the game would reduce the artificial lengthening from around 30 hours to around 10 hours of gameplay.
And as hard as I tried, I just couldn't care about any single one character, let alone the group.
If gameplay was tight and involving, I could have forgiven the story. If the story was interesting and the world was better established, I could have forgiven aspects of the combat. But I honestly think that no matter what my opinion is, anyone can bleed water from a stone if they try hard enough.
I think this game might have actually been much more well-recieved had it not been a main series Final Fantasy. The problem is, because the series of 13 games has had increasingly diminishing returns, we face the very real possibility that Final Fantasy XV could be the Final, Final Fantasy as most Japanese developers are abandoning the console market and instead working on portables and mobile devices. And that's why I think I wrote this poorly constructed mess of things I think would have made 13 work better. Because I don't want to see this series die. I don't want a 7 clone. I want a good story with good characters and a challenging combat system that makes me feel smart when I set up my party and equipment and commands just so.