Amazing work! I've seen a couple of Rebel briefing dioramas over the years, but this one really shines in comparison. I agree with you that we need some more Rebel Pilots, though. There are at least a couple that might fit your diorama well. Namely, Nien Numb, Arvel Crynyd & Ten Nunb (POTF2 Rebel Pilots cinema scene - uncustomized
) and the pilot from the SAGA A-Wing. But I can see just as much value in not cluttering up such an awesome diorama so that you can take in some of the details.
I don't know if this idea would fit with your overall concept, but one thing I've been doing in my Rebel briefing diorama is the use of a couple of old accessories. The big one being the planet Endor itself, from the POTF2 Complete Galaxy series. And the other being the holographic Death Star 2 which was packed in with the POTJ R2-Q5. Those might totally take this piece over the top, although the opaque Endor might be a distraction since it's meant to be a transparent hologram.