I've often had the debate with owners or merchants regarding exactly how sensitive these cars, and especailly their owners, can be. I think it stems from how solid, well built, and precise the cars are to begin with. If there is one burr in a satin sheet, you will feel it. If there is a burr on a burlap sack you probably wont notice. Drive most any mundane car to triple digits. Assuming they can even make that speed they are darty, unstable, and shake like the proverbial "bowl full of jelly". Virtually any benz (sorry 240D fans) can cruise at triple digits for hours in a completely dramaless fashion.
I will defer to the wisdom of suspension guru MB DOC for any analasis of the suspension. For a quick check if that rim is the culprit, or at least how much of a culprit, try putting the spare tire on the suspect corner. The small difference in tire type should be inconsequential compared to a rim that is out of true. You said the one rim had scrape over 50% of it. Logically that would mean that the weight balance of it is off at the very least. If the wheel is off balanace and you have a "egg shaped" tire it could be quite difficult to get a perfect balance on that corner. Put the spare on and see what happens. (assuming it has no obvious curb damage)
Best of luck, and keep us posted on how it turns out....Lee