Even if there's no handicap system, after the first resort faster guys will race faster guys. So I don't think that's will be a big deal. I know when I first started racing I like racing the fast guys it made me faster.
How many people are going to show up on Sunday? I'll like to be able to race. I will be there at 9:00 AM.
As for tires I would run sorex 28 in the morning. But by main times I'll use sorex 32, and maybe 36's if the temp is above 30C. If it hot out I think the 28's will burn up in 1 or 2 heats.