Something to consider for the faster group would be a Pro206 . Take a LO206 and change the cam to a progas cam and the rod to a WF then add the WF coil (7100 RL).
ALL OTHER specs stay the same as LO206. Easy to tech and faster than a 206 BUT not the cost of animal or progas. The 7100 rev limit makes it a hoot to race and saves a lot of wear and tear.
The rules are already basically written. Take the LO206 rules and change the cam specs to teh Progas spec and ADD the WF rod and coil spec. Bingo done deal.
Maybe Briggs could offer it as a SEALED option to the LO206 platform as the Pro206. They would ONLY have to Exchange the coil,cam and rod. It could come race ready for a reasonable LOW cost.
Now that would be a good low cost factory option in my opinion.
(;-) TP