Don't worry about season prizes, decent prizes for each event is much more important. Trophies for season is plenty.
Insane is obviously a great location, but I think expanding some from there would be a good move. 5 events is perfect, 1 before each PSP like yall have done.
IMO, you should keep 2 events at Insane, 1 in north georgia (Nitro), 1 in either ATL(Dosser) or Mid GA (Big Indian), and 1 in northern Alabama (Prime?)
As for paint- $45 a case is decent and puts everyone on an equal playing field- but that makes it pretty rough for D3 since it is Raceto4. I would suggest either offering slighlty lower paint price or BYOP option for D3 since more paint is being slung. Or another option to lower cost would be to drop down to raceto3 like d4. Don't drop down to Raceto2 for d3 though, this is the only place for ppl around here to play x-ball format.
Looking forward to trying out MILP next year, heard only great things about reffing and smoothness of the events!