JR, any chance you and Sterling would consider building a Retro upper, with the right hand side S-shapped bolt carrier mounted charging handle and partial dust cover like Brownells version? Hell maybe you can even source some of the parts from them and PWS... there seems to be a lot of interest for this between your threads and IRG's Nodak/PWS 180 vapor ware thread.
I would happily buy either a kit or full upper to have this configuration.