The one that gets to me in a bad way is graphics related. There's nothing wrong with the zones or anything. They're beautiful. What bothers me is that everything has a rather strong golden lighting effect to it. I'm sure it's a setting somewhere, but I can't find it. It makes things look as if it's late afternoon and there's a bright, almost harsh, pre-sunset light on everything. It kind of bothers my eyes. Since it occurs everywhere else I've gone (Orgrimmar, Mulgore, and Thunder Bluff) I figure it's some global effect. It gets to my eyes after a while.
Try this command:
/console ffxglow 0
There used to be switch for this in the graphics options menu, but it was removed in Cataclysm for some reason. Basically, "ffxglow" or "Full Screen Glow Effect" (as it was once called) turns off/on the bloom effect we get from the sky and ambient lighting. Depending on the area you're in, the effect can be either really noticeable or not noticeable at all. Well. Relatively speaking. Personally, I find that it adds a lot of life and vibrance to the scenery, but this is about making the game more comfortable to play.
Turning this off can also improve framerate. In fact, I often turned it off when I raided ICC on my old computer so I could fight with better frames. Anyway, give this command a shot. See if it helps!
*PS: If you haven't figured it out, /console ffxglow 1 turns the effect back on. ( 0 = off; 1 = on. )