Nordic I like your suggestions too!
1) Yes, small manufacturers like Lister/Saleen/Spyker/etc... should have a chance to be represented.
2) Great idea. Perhaps a price cap?
3) and all funding comes from national governments? Or people who sell green/red/blue or silver products? How about first choice of pits to teams in national colours. Or automatic exposure on the race posters?
4) Nice! With a performance break?
5) As long as they drive it single handed! And why not drivers over 46?