I think you've gotten it fairly close. Just as a note, here are the two main things that still remain to be tweaked:
1) The ability to 180 grind a number of times in succession. This surely needs to be reduced, for all the usual reasons. In my opinion, a single 180 grind (maybe two) before exploding would be optimum. I dunno how to alter this.
2) Rubber feels about right at slow speeds, but becomes very touchy at higher speeds (I've previously noticed this in other beta servers as well). One could argue that this is a good punishment for speeders*

but it probably shouldn't be nearly as touchy as it is, especially if trying to replicate the old Shrunkland. I think we discovered that changing (I can't remember whether you increased or decreased)
cycle_rubber_speed fixes this?
Other than those two things, I can't really think of anything off-hand that was really off.
* No, I don't mean the clan specifically.