It's interesting--he wants to be quarterback NOW, because of how happy I was at that completed pass! But, prior to that, none of them want to be quarterback. They all want to be the running back.
But the favorites issue *is* problematic--our smallest player is my assistant coach's son, and he probably gets a bit more time than he otherwise would. That said, he has more heart and puts more effort in than anyone else on the team (with possibly one exception). So, it has worked out. The funny thing is, he's got pretty good moves if we let him run it, and he's *really* good against the teams with the bigger kids. By virtue of being so small, they have to bend over to try and grab his flags, which makes it quite a bit harder for them to use their size/speed against him.
I find that, favorites-wise, the players that give me the most trouble are the ones I want to play the least. I do my best to be mindful of that and give them a fair shot anyway, but...they make it hard sometimes!