Some more info on this topic.
Famous large projects like KDE and MySQL already migrated to CMake.
Here are some noted from MySQL:
With autotools, to correctly build a project, you have to know autoconf, automake, libtool, autoheader, m4 macro, shell script, and even more... When things go wild, there is no easy way to hack it since it generates several thousands of non-human readable shell scripts. The scripts are even bigger than the actual source code of our programs. Autotools is just a nightmare!
I will do more research on this. If all experiments yield positive results and we can solve all the problems, I'll consider migrating to CMake, starting from small components such as lxinput.