This thread is quite extraordinary. Carbon squishy? Carbon offering responsiveness that steel cannot match? Carbon stiffer than steel? Custom builds are a crap shoot?

None of these generalisations are correct. i have steel bikes that are phenomenally stiff, at the expense of being somewhat heavy. I have a carbon bike (Giant TCR) that is plenty stiff. The "responsiveness" of these bikes is governed by their geometry, not their frame material. I have a custom steel bike - columbus spirit frame, carbon forks - that is light and fast, handles better than my TCR, and is a little less stiff.

A decent framebuilder will build you a steel bike that offers the stiffness (or lack of it) and other characteristics that you want. But it sounds as if the issue here is not frame material, but merely finding a bike that you like.