Well, I'd ask things that would lead to a Pokemon one would likely like to play. I'd ask things like favored types, moves, a stat they value (So if you say you like fast Pokemon, you'll likely play one.) A personality gist (which will be crunched down to a nature.) and maybe a few other things. Then I'll ask for a list of favored and unfavored Pokemon from the trainer(s), and return a Pokemon or two for the player to fill in a CS.
Also I currently resemble that remarxKORP!