The real big problem with MCC is the unified interface they created which was poorly done, and that the whole project was mostly outsourced during development... hence why it was so broken at release, and still not in an ideal state even now. If they couldn't manage getting the unified interface right and were even just a little smart about it, they should have just created a main menu for launching the games separately, then there would be less potential problems down the track. Alas, that ship has already sailed... and sunk.
Right now I'm just a little excited to see Halo 4 come into the BC program... because ALL THE MODS! (I mean gametype mods of course). It may not look as pretty as the MCC version with sub 720p res and 30fps, but I will gladly trade all that for more fun and crazy customs with gametype modding.