This is difficult for me because I am not an asker. And I'm definitely a must-do-everything-myself-er. (It was years before I was comfortable even asking my partner to make me a cup of tea.)
* Invitation from an artist to collaborate on a comic or doujinshi. (I can't imagine having the nerve to ask an artist this.)
* Concrit on my writing. It's not something I would ever offer unsolicited to anyone but would love to have so I can see where I need to improve. But it's a big time commitment to ask for and also makes me feel like I'm being, I don't know, presumptuous, maybe?
* Art of Mitsui from Slam Dunk as a hockey player -- in a hockey sweater, with proper hockey hair, and all his missing teeth showing. (Maybe with Kogure in the background as his manager!) I've been daydreaming this one for years!
* For people to feel free to make requests of me. :)
I also put up a Transformative Works statement on my AO3 profile and my LJ/DW sticky posts; should have done that ages ago.