It's interesting that you and I think along some of the same lines. When I picked up my used M3, I made sure it was a 6MT, as I had (and still have) reservations about the long-term reliability of the DCT w/higher HP. Drew's build verified that I was right to be concerned. Granted, the DCT is faster, but I don't feel like replacing a tranny every couple years.
I've been looking at the HP to $ ratio of making respectable power out of the M3 w/a supercharger, and have been extremely disappointed w/the M3 tax burden that is placed on us. I understand that you have to pay to play, but I can't quantify that kind of $ and then getting stomped by so many cars on the street and the track.
My end game is to finish out the M3 by the end of this year w/a used s/c. Mid next year, I then plan to buy and start building a 1000-1200rwhp 6MT MKIV. That'll satiate my desire for an overall street/strip/rolling fast car