I know in ranked games, a characters elo determines the order of champion picks. In non-ranked draft pick, pre-arranged teams have priority. Does team size, elo, or anything else affect the order of champion pick?
AFAIK, the ranking only considers premade teams vs. solo queuers. Premades get higher priority (order randomized within the team), then any stragglers get randomly thrown in underneath them. This is why you end up in the bottom 1 to 2 slots so often if you solo queue for normal draft pick games - you're getting matched up with a pre-made (or 2).
I don't think that there's been any official word from Riot on this though, so this is all conjecture.