Son of a-.... While I've been taking time off, you have been absolutely charging ahead. Dayumm..
So much to comment on! That interior looks stunning, you really did a good job on those shadow shapes too.
As for the silhouettes I like 4 12 and 16 the most, very interesting looking. Something I found out from silhouettes, and something I have heard other people say, is that you should avoid them until you are very confident, so that you can turn what you see into proper forms (don't know if you will find it the same though ). I struggled for so long with trying to make forms read and get what I was imagining on to paper. It was a good exercise though and I learnt a lot.
Which masters did you use for those mountains, they look really good, I love studies like that, that look like a window on a neutral grey background.
Those hand studies from pictures really look good.. Hands are a pain in the ass, seriously.. I don't know why they are so difficult to draw, but spending time getting them right is definitely worth it.
And those two figure studies way up, excellent as well, you truly are making leaps and bounds in your progress! Keep it up! I cant wait to see more