Hey Pilot

Okay, Well I've been mulling this over, and heres a suggestion.
Make Sure that your weights are as good as you can get them for the body only, for your bends and twists etc, but as for your armour on the front body plates, keep them parented and then why dont you make a blend shapes or 2 and drive those with the back bend controls or whatever you have on your rig.

I've been doing this method on some characters at work recently on the clothing as I dont have the time and patience to run cloth set ups!!! It works really well, let me know how you get on.

Also for character set ups, I strongly recommend two really cool books, one is Maya Character Animatio by Jae-jin Choi and the other is Maya Character creation (Modelling and animation controls) by Chris Maraffi

These are well worth it!!! Hope this helps

Jango