Well the story starts slow, and is full of terrible fillers, so that doesn't help. I think the first primal fight is pretty nice though, the build up isn't the greatest but it looks really cool and gives you a decent taste of how they do their story stuff(iirc it's around lvl 20, after Halatali or something). Then for whatever reason, it's fuckshit nonsense for the next 20levels, fucking Titan story arc is the worst, minus the Lalafell pimp in Costa, but once you're done with this shit(and you should absolutely skip everything during that arc), only then it really starts being good. You start confronting the Empire, Garuda is epic as shit, and the end of the arc is really epic too, though sadly nowadays you'll get rushed through the dungeons and won't be able to watch cutscenes, which kinda sucks(can watch them after the dungeon though, overall the idea was retarded and they should have fragmented the dungeons in smaller parts and left the cutscenes outside).
Then once 50 you have some new arcs start for each patch, some are pretty bad(Moogle, Ramuh), some have really cool stuff in them(Leviathan) and the last one, Shiva/Heavensward, is getting really great. The coil shit is great too, especially Final Coil, though at this point it's probably unlikely you'll see these besides watching them on youtube or whatever. It even has CG cutscenes.
Do skip text on all side quests, watch the stuff for your class assuming your class isn't one of the terrible ones(bunch of them are to be fair) and watch some of the story but mostly skip most of that too.
As for clunkyness, could be lag, could be bad FPS, could be the longer GCD. It's a bit weird to play at first but I really like the slower GCD overall. Maybe cause I'm getting older so pressing keys every 2.5secs instead of 1.5secs is easier/more relaxed.
End of the day though if you don't like the game, you don't like the game, plenty of people don't like games that other people like, it's kinda up to everyone to decide. The game is in my opinion one of the best mmo, mostly because of all the content they keep adding and the art(music/graphics/animations) but I can totally see people disliking it because there's a bunch of aspects that are polarizing, like the slower combat, the fact it's a wow clone, the non customizable UI, the over reliance on server checks for everything leading to abilities getting cancelled/played in the wrong order, the recent bad connectivity to their server(though I'm pretty sure that's an american problem as I rarely have any issues, probably Comcast or whatever being bitches and fucking up somewhere).