Yes, it's changed significantly. You can solo to max level if you choose since per-kill XP has improved and you get regular XP bonuses through "Field of Valor" or "Ground of Valor" pages. It inevitably had to do this for the players levelling multiple jobs, as the "old way" could be a very tiresome (if fun) grind. I miss it personally, but only because I only ever made it to like 40 back then, didn't get to play so much back then.
The biggest problems in XI are the extremely dated UI, very limited macro usage (which can be solved with an 'add on' but is still somewhat of a bear to really get right), and eternally clunky mechanics. Switching to combat stance from out of combat still has a long delay, so does crafting and gathering and menu changing, etc. I think they're working to retrofit a modern UI to it which I think would do wonders, it's still a great game with lots of content. It's just mechanically very dated. They've shown they can fix some of it with the last (final?) expansion which has much improved gathering and map/world navigation, but how much of that can be retrofitted into the rest of the game remains to be seen.
But even then if they get all of that right, I still feel like the combat and gameplay can only support so many bosses/encounters/endgame. Most of it is just zerged and has been quite trivialized, I'm not sure how much more can be done to make the encounters unique this far into the game.
Subjectively, I would say it does. I would load GW2 on my HTPC (dual core athlon CPU, 4GB RAM, Nvidia GT240 GPU) to watch the auction house and did the same with it during phase 2 beta of FFXIV (crafting and watching the market board). I feel XIV ran more smoothly than GW2, but there were usually fewer people on the screen as well. I did notice that even though it defaulted to 1366x768 on a 1920x1080 screen, it still looked quite nice as well. And the default 'low' options were intelligently applied imo.
PVP will probably be elective. There is a PVP entry on the character screen, showing your 'rank' of some sort I would guess, but it will probably be arena/battleground only setup, there's basically no way they're going to make it open world.
Combat is pretty much typical. Your character auto attacks, you press your hotkeys, special abilities happen. I haven't tried a caster yet though, and I definitely noticed in phase 2 that when you levelled up more and started being able to obtain more sub abilities from other classes and had more buttons to press, it became much more interactive. Further, using an ability expends TP, which adds another dimension to combat beyond simple "cooldown rotation". TP is similar to energy for a Rogue in WoW if that helps.
Limit breaks I think have taken on another meaning in XIV (compared to how the term was used in XI, at least). Currently when your party is together, depending on it's composition, you can perform a "limit break" (based off some resource accumulating, not sure what) which is essentially kind of like a magic burst or skillchain, except depending on who initiates it and what classes are in the party, it will have different effects, offensive/defensive, single target/aoe, etc.
If they develop content for XIV anything like XI, there will be an abundance of mini games and activities to take part in eventually. Currently crafting and gathering are really interesting, they're like a turn based RPG in themselves. I absolutely loved them in phase 2, didn't see if they changed in phase 3 yet or not. There's also plans to obtain your own chocobo which I think can take part in combat with you, I would expect that to have some amount of breeding/raising/training activity attached to it. I think the extracurriculars will probably come later rather than sooner, but SE definitely didn't overlook them in XI.