Again, I feel your pain... If I had any sense, I would drop the SM idea and go for an ITA CRX or an SRx7.
1. Al and SRx7: Everytime I talk to Al, he tries to con me into SRx7. His car is slow for HPDE, but mid-pack in SRx7, so while it is no fun getting passed a lot in the instructor group, it is a blast for racing. Add to that that its cheap and you've got a winner. Sadly, I just don't like 1st Gen Rx7's -- which is why Al makes fun of me for shopping for a yuppie race car (guilty). The only problem I see w/ SRx7 -- if you don't mind the car -- is that the classes are strong now, but shrinking as more of those guys go to SM. It also means, however, that built cars are cheap -- I know people who've bought turn-keys for $3500
2. I suffer from RWD envy also. The smartest thing I could do is buy a CRX. They are cheap, easy to set up (and there are a lot who will help), competitive in their class, and you can run in ITA or HC. I owned a Civic -- I like RWD that much better. It took me a while to get over the 240, but after I drove a Meeoter, I *got* it. They are more fun -- period -- even if they are girly.
3. As far as running in the front -- you won't. Not for a while anyway. For the money, SM will get you the most competitive car. A shabby ITA 240 will be killed -- I'd wager it takes about $15-20K to develop one to run near the front. A bit less for a CRX. There aren't many SM's w/ over $20K in them -- most are about $10 or less. The basic package takes about $9K, after that, the only real benefit is a pro-built motor (that will usually only get you a few more hp). In short, you can reach a podium for $10K. The only other place you might do that is HC when none of the good ITA running H4 guys show.