If you want to exclude the RE-71R in SS classes, just do that instead of trying to regulate it through TW ratings (which are admittedly easy for a manufacturer to fudge). The RE-71R doesn't come stock on any Porsche, so it won't affect anybody who comes right from the dealer. There's plenty of evidence, not just locally, but all over the web if you look for it, for the idea that the RE-71R is more like a 100 TW tire with regard to performance.
I happen to think that it's okay for the RE-71R to be SS legal, but I'm probably a bit tainted by the fact that I started autocrossing with the SCCA in 2003, when being competitive in Stock class meant buying Hoosiers...
Having the RE-71R available seems like a godsend to most of the SCCA folks. In addition, just about everybody who has tried the RE-71R tires loves them; if you want to encourage tire manufacturers to make tires like these -- and I do want that -- then make sure that your autocrossers can buy them so they keep making them, and even improving them!
That being said, and I brought this up last year when we were discussing this -- with the possible exception of GT3/GT4 models, I don't think Porsche really delivers any of their cars with autocross-ready tires. It's not that they're not competitive; it's more an issue of the tires not being able to stand up to the demands of autocross, especially on a somewhat abrasive lot like the one we run on. My factory-delivered tires lasted 4 events (1 SCCA weekend, 1 BMW event, and 2 PCA events). They would have probably failed tech if I had tried to bring them out for a 5th event. My RE-71R tires were faster than the OEM tires and they lasted longer: 6 events, and I mainly switched them out because the season was over.
As much as I'd like to think that it's a noble goal to have cars be competitive for autoX as delivered from the dealer, I don't see it happening -- and it's not because of our rules, but because Porsche delivers tires for the sweet spot of their market. (Competitive autoXers probably make up what, 3% of all Porsche owners at the most?) The only cars delivered in a reasonably decent shape to go autoX are the GT3/GT4, and the proposal to restrict SS to 240 TW or greater would essentially eliminate the GT3 and GT4 from SS. If I owned one of those, I certainly wouldn't put 240 TW tires on it.
On the issue of PSM and whether it's a competitive advantage -- I'm sorry that Ryan and Andrew haven't had the chance to drive a really good modern PSM implementation.
I generally run at least one run at most events with PSM off -- and usually more than that -- and generally find that turning PSM off actually costs me about 0.5 to 1.0 seconds per run compared to driving with it on. The issue is that with PSM on, I can drive at 10/10ths and rely on the PSM to keep me from getting into any sort of nasty trouble -- when it does kick in, I'm usually pretty thankful that it did. With PSM off, I'm driving more at 9/10ths, because even though I can correct a loss of grip, it probably takes me at least half a second to react and correct it -- with PSM on, by half a second, the problem already got solved.
For me, the biggest issue with a point penalty for PSM as proposed is that it will be practically impossible to enforce a penalty for using it. If the Zone wants to change the base point value for modern Porsches to reflect the better PSM implementation, that might work.
As to Launch Control, I've taken both my Cayman GTS with launch control and my Evo 8 with a race clutch to the RaceLegal drag races at the stadium. My 60 foot time with the launch control Porsche was 2.192 seconds. My 60 foot time with the Evo 8, with no launch control, no traction control, everything manual, was 1.773 seconds. That's an eternity in drag racing -- 4/10ths of a second. Launch control is nice -- but it's not some sort of black magic that finds traction out of nowhere...