The old, they’ll never think to look for us where we had a secret base forty years ago ploy. 😉
Leia took a page out of Obi-Wan’s book, The Art of Hiding in Obvious Places.
Yeah, I think that is Yavin IV (I recall reading that they considered making the Resistance Base in TFA Yavin, which is why the base interior looks very similar to Yavin, with roots growing over the stone structures), and I think the crashed Death Star is the DSII, and the environment is just more variable on Endor than it is on your typical Star Wars planet.
Honestly, what they’re doing with Leia is one of the things I’m most excited about. Just seeing how they pull it off, regardless of how much she is in there, is pretty incredible. Because it isn’t a situation where the actor died during production, like it was in the cases of Bruce or Brandon Lee, Oliver Reed, and Paul Walker. This time they are actually using unused footage from a different movie to have a deceased actress play a roll in a film she never shot anything for. I hope the home release has a in-depth look at how they accomplished it.