ok, one of the reasons why nothing gets back ported to the campain is because adding anyhting systematic to it WILL unbalence it. so what if we start makeing stuff new for the main campain, modify some of the weapons to use new effects/features (maxim useing ammo for instance), maybe add a few new missions that would allow the use of things like SSM, and we go in and rebalence everything. if any new cool gameplay features are developed, we can patch them in as well.
now, this wouldn't be a new campain, and it would not be generaly closed as most campains are (when ever a new version of a mission is made and is done it will be publicly available) and it would not realy be 're-makeing' the origonal, most of the time the changes will be minimal.