The only real problem that I have with CF in things like a chassis is that it doesn't conduct heat very well. I depend on my chassis to help move heat away from what's important.

As far as an "upgrade" for the chassis goes, it would need to be one of two things to be really better. Either thicker or made of something harder, like 7075. 6061 is actually really soft. I did a little test. I held a 1' long 1" diameter 6061 rod at shoulder level and dropped it on the concrete and did this a few times. It dinged the heck out of the 6061. I then did it with a length of 7075 and it hardly dinged at all.

Of course, 7075 costs more and is harder to machine.