My pet peeves...omg so many over the years! Just to name a few:
AO's with weird walks (you try them out and you like everything BUT the walking animation)
The price for mesh heads (I'm just frugal...this is not the only price I have an issue with lmao)
Forums turning defensive (people really just want to post and talk about what they post...people act like piranhas sometimes)
Flexi hair (why does it move like that???)
The Marketplace (by now it should look different, like updated, right?)
Lol there are probably soooo many more.