Was rereading part of this thread today and veering back on track (no pun intended), to me a good path would be:
1) Allow an overbore (.030?) and the subsequent compression increase (makes more blocks viable w/o sleeves) - keeps the head "as is" and allows lower cost first build of junkyard block (vs. sleeve)
2) Allow an alternate carb on the stock intake (several have been mentioned in the 36 - 38 mm range) - sub $300
3) Allow any 5.7" rod w/any flat top piston that does not exceed the stock deck height (allows competition)
4) Require a spec rev limiter w/ a spec chip w/larger carb- (extends lifespan of motor).
This would seem to be a (relatively) cost effective package that would allow a modest performance and durability upgrade.
Just my $ .02