I voted for improved gameplay. As much as I have gripes with the story, at the end of the day this medium is a game and the gameplay needs to be good, which it isn't. Not very. The extreme amount of cutscenes compared to actual gameplay reminds me of FF9, where the gameplay was really meh and they tried to distract you from it by dazzling you with cutscenes, but once you're out of the cutscene heavy sections you're just confronted by lackluster gameplay. I don't feel like I'm exploring the world. None of the zones feel dangerous. Combat doesn't feel dangerous. Combat feels like a snooze fest. Running down a 15 minute long corridor isn't a very fun dungeon experience. None of the classes feel super fun to play (at best some look a little flashy and some have tolerable gameplay, but I'm never really thinking "Wow I want to have fun doing this class' rotation!"). And so on.
It would be cool if there was engaging non-combat gameplay. In GW2, there are sidequests like helping kids gather up snow and armor and build a small snowman army around the perimeter of a village to scare off beastmen. Or stuff like testing rayguns or mechas and temporarily getting a new hotbar of abilities (WoW also does this a lot, like riding dinosaurs or giant yetis and smashing armies). Or the adventures from the HoT expansion where you can hang glide and ride jet streams trying to catch bugs, or the jumping puzzles (some give you movement abilities that make them more interesting), or the mount racing, etc. Traversing the environment was also a challenge and fun with the bouncing mushrooms to jump on, trying to find jetstreams to glide up on or hidden passages, etc. It would also be cool if the world felt dangerous, like if you're level 16 and you're running through a field and you see a humongous level 80 dinosaur and there is no way you could take him on yet, so you have to run around him and keep aware of your surroundings, and then one day when you're strong enough you and others could come back and fight him in an awesome battle and get loot (you never see a powerful rare mob on accident, and the world bosses are secluded in some location only endgame players can reach). Don't think the boring rotation combat will ever be revamped.
If GW2 can add in a zone in every patch while doing system overhauls on top of that (the expansion patch content usually has more content than the base expansion), I don't see why FFXIV can't either. And FFXIV requires a monthly subscription fee.