re: How big your party?
We generally have 8 PC's with 3 players controlling them. Combat-wise, we're usually limited by our DM to 5 PC's engaged in combat with the exception of the occasional supporting healing spell or such. Since, I'm the only player with actual copies of the core rulebooks and did more than skim them, I'm generally the one who controls the extra character or two. The number of people in our group seems fine and allows us to specialize while also allowing the DM to challenge us by sending creatures and traps with CR's just a level or two above our party level. The irony of the situation I'm in right now is that of all the guys who played D&D at my school, most of them quit for some reason or other, refused to play anymore, and the only ones who continued to play were not very "capable" at DMing or playing or very trustworthy. I ended up having two girls volunteer to play and having the only DM at my former school that still plays D&D. I'm not complaining but I find it ironic due the stereotype of the "typical" D&D player. I will complain about the annoyance of scheduling conflicts even during the summer.