Abstract icons are random, I did a set of them a while ago, but they aren't too appreciated I think. I think a majority of people (here at PC anyways) like seeing people and anime and stuff. It can be good practise to try new things though!
Grats on 3 years also! I got to veteran like a few weeks ago cause this isn't my first account, so the join date is wrong, but that got kinda skipped over. :P Oh well. :D