Here are other ways to Build a Better PC, following on the ones I listed in these posts:
Building a Better PC
and the posts linked here:
Stuff I Like: Being a Better Player
One of the reasons I can play with such a large group is this trait of my players:
Offload From the GM
The GM has a lot to do. The GM is the bottleneck of play - and the GM's attention cannot be focused on more than one area or one player at a time. The GM is needed to keep things moving - it's a GM-centric approach to play.
Because of this, any administrative tasks the GM needs to perform take away from time that could be spent focusing on resolving PC actions. It's valuable as a player to limit the amount of admin a GM needs to do.
In my own games, for example, my players offload the following:
- rolling to hit and damage
- effects of damage on PCs
- calculating margin of success
- tracking consumables, loot, and encumbrance
- calculating spell costs
- calculating and tracking spell energy recovery
- timing of spell effects
amongst other things. This allows me as the GM to focus my attention where the players can't fully offload the task from me, such as NPC actions, arbitrating decisions, and describing the world.
The more you can take off the GM's plate, the more smoothly game can run.