It may be poofing so much because of damage from the straightening. I concur - try the CG method focusing on moisturizing your hair. Try leaving some conditioner in your hair when you rinse or scrunch in some extra after you rinse. You may be amazed that your hair loves it. If you are accustomed to shampooing you may feel more comfortable with modified CG for a while (that's using a lo poo like Deva Lo Poo) instead of just washing with conditioner.
I agree that your hair sounds beautiful. Thick is good in my opinion - I have to use Rogaine since my hair started thinning.