As an outsider looking in on this thread for some time now, you guys are all to be congratulated on your efforts to form the Social Club you all want!!!
But, my opinion is that you have forgotten the main issue at heart here, social racing!! You have done this by making too many rules and guidelines for a small get together group. Whilst this is not to condemned, make the basic classes simple for the beginning of this new adventure and enjoy the social racing and companionship you all desire.
If it was me forming a small group like this, pick 4,5,6 or however many real championship classes you desire and make those races for stock cars only, no tyre changes, no this and no that. Straight out of the box, that is fair for all and as the group grows and improves the rules can be revised. You as a group have gotten ahead of yourselves and made it all too hard and are on the verge of imploding!!!!!
Not forgetting that you can have social races as well, but they don't count toward the end of year championship points.
Just my opinion and good luck with the social racing.