This is exactly how my 2aw works currently. 2aw code and data is just one mf file. I have a simple loader which just starts the code in the mf file and even unpacks with some c++ extension. All data and code is in the mf file so its easy to patch. I actually have a blue print for this already and have though about the problem:
blueprints.launchpad.net/panda3 … ntime-only
And as you notice is an old one.
Also about distributing C++ code, there is platform independed but architecture depended way to pass the code around as compiled objects which are linked to the proper os libraries during linking stage… i mainly seen this with x86 assembly projects though not the c++ but it might be possible if the packages use only the panda3d functions.