Home tournament chip structure

[CashinCam]

I'd like to know a good starting chip structure for a game that consists of approximately 10-12 players. I have a 1,000 chips set with 300 white, 300 red, 200 green, 100 blue, and 100 black. What is a normal starting chip stack if we start the blinds at 25/25 or 25/50? We've been starting at 5/10 with 20 minute levels and the game just lasts too long. We normally start with 2,500-3,000 chips. Any suggestions? Thanks a lot.