I'd rather have three or four options that I understand, and then have opportunities later to make further choices, as I know more.
If this is a 30 minute game, then it doesn't matter so much. I'll be playing it many times and thus come to know what the choices mean.
I agree, having a few options that spawn more options further down the line is good. That said, for fast paced games, the character selection in Necrodancer for example has a number of options that come with different playstyles, but since each game is generally only several minutes long it feels nicer to have that level of choice.
If you did want a large number of playable characters in a game thats more than several hours long, having them unlock as you play and accomplish things could be a better way of going about it.
Again it depends on the exact type of game being made and what feels best.