I don't want to change the default. Keeping fast startup time is a nice goal!

I'm asking to make it configurable for my own development workflow: build Python as fast as possible.

It is easy to hack Makefile.am.in and Python/frozen.c to freeze less modules. If you want, I can try to work on a patch to make it configurable. Maybe some people want to freeze... *more* modules, rather than less ;-)