Ignoring the material question for a moment; what is it you want to achieve with this bike?

Two things have put me off buying carbon. First is that few fit me. Second is that if I equip one for the type of riding I mainly do, then 90% of the bike would be the same as what I already have. That leaves little room for improvement, so surely would be disappointing.

But maybe one for short fast rides, or a mountain goat? Don't have that, so if deciding to do that, then might as well pick the best kit for that job, which might well be carbon. Very achievable.