ya. i'm sure you could compile a more complete list than that.
my intent was to give the OP a bit broader idea of just exactly how versatile the platform (and his lower) can be.
one suggestion there barrel - build your uppers complete.
the ease of being able to just pull the takedown pins, swap the upper and swap mags is awesome - even in calibers that would share the same bolt carrier group... like for example 204, 223 and 300 blk.
plus then if you do happen to have a failure on your BCG you have extra parts you can swap over to keep you going on a range trip as a worst case scenario.