sure, i see where you are coming from. but the four-link will need it's own sub-frame, which would be tied into the cage, which would be tied into the front sub-frame (the thigh bone is connected to the...) and who says a torque arm can't be used with the four-link? i saw a killer torque arm on banks' site that looked like it came all the way up the trans tunnel...
while i'm mostly just bench racing at this point (it's all bench racing until you actually buy something)...
i'm definitely looking to over-engineer it. if i never need the flexibility of moving the instant center, so be it. however, if i do, i won't have to say "now, why didn't i do that when i had the money and the car in so many pieces..." i don't see it as a wasted move - more like getting a head start on the inevitable.