The biggest thing i'm worried about still (and even now) is the lack of content. If 2.0 launches with a graphics overhaul and no new content (or limited new content) it will fall flat. There's only two patches left from now until the tentative beta 2.0 launch. That's a long stretch of time for content. Why would I want to get on 2.0 with hardly any new content?
I also want too see more variety of zones that have imagination. I'm tired of the basics used time and time again in all of these MMORPGs. I want to see fantasy. I would like to fear my surroundings, and that of my enemy. Neither of these exist in 1.0. The floating lakes of Sian Sian sound amazing, and I would really love to explore that place.
Lastly and probably the biggest of all my concerns is the main scenario. Simply put: It sucks. This is not a Final Fantasy storyline, and I really want to see them scrap it and start over. They had really good quality story-lines with CoP, ToAU, and WoTG (especially). The normal quests don't have enough cut-scenes, and the rewards are beyond lackluster. Experience points? Woot, oh wait i'm 50 already. I would like to be rewarded with recipes, new quests, key items. I don't care really.
It's really hard to not get extremely excited for 2.0 because it is the second chance to make this MMO into the amazing game that it should have been. However I also know that I got my hopes up once, and I got kicked in the groin with the original FFXIV launch.