Not suggest to pay too much on options for FW06. That is a black hole!
But I know modification is very interesting...haha...so I suggest below. (I assume you play in street?)
1)Anti roll bar set
2)Spring set (original is too soft I think)
3)Screw set to adjust down stop
4)Re-build the rear differential and change better differential oil.
5)Chassis (but can change when the original is deformed)
Above modification is not high cost one but you can see the difference easily. For those graphite parts, for a beginner, you can feel the "outlook" change only...
yes I agree with your suggest items. I am not dare to throw too much money on this FW06, if I do so, I prefer go for V-one level .
by the way, which shop has above option parts for the 06? thanks!