Don't read this if you don't like random rubbish :) I have capitalised my mains if you don't like reading ;)
I happen to have quite a few mains, obviously i have my favourites but with the chaos of solo queue you have to be prepared for every role whether you like it or not. My main role is ap, often my mains are ap no matter which lane but there is the obvious exception of the AD carry and sometimes the jungle.
Top lane: My WORST lane, if i get stuck top can do ok. Definitely not well but i will farm and often accidently push because i am the worst player ever clearly. The only top lanes i can ever think or trying are VLADIMIR, FIZZ or AKALI. All bursty, all capable of inflicting pain but not always the best when you have an AP mid or bad jungler.
Mid lane: I would call this my best lane but again, I inevitably push as i main MALZAHAR and again FIZZ. This can go downhill as fizz (I don't often lose lane as Malzahar ;D) but either way, wrecking late game is easy as these 2.
Bot lane: I do ok, my carry role is TWITCH, no one else. Twitch even after the nerf/buff (whatever you want to call it) can destroy pretty much anything after he gets an IE and his ult... oh his ult <3
As bot I will also take my Tank/support main too which is LULU. Often in pre-game chat i will say ok "ima tank Lulu" in which the response is usually "OMG WTF TANK LULU WHUTTTT?!" but it is hard to do badly as tank Lulu with the global taunt situation going on :)
Finally, my generally bad role, jungle. I don't know why i try to jungle... underleveling is often the case with me but ganking is fine as my main's are SHACO and NUNU. Mega trolls in jungle whether you suck or not and these 2 are often unstoppable by the time mid game comes around.
There, my mains. If you main some weird champs in some weird places, tell us why so we can all be a little more prepared for those who are good and those who are trolling xD