I can't be certain, but I think I'm either on pace with you or a little bit slower. I'm at the beginning of Chapter 6 with 15 hours of game time!

Whenever new crystariums are unlocked, I purposely will not push forward until I run back and forth on the current map, eventually gaining enough CP so that I am maxed out (not able to use any more CP). Its not until this point that I will then move on.