I like your block, and am glad that aren't taking over his room. He still needs a room to come home to on school vacations. To take over his room at the present would be like you were shoving him out.
I remember when years ago we left our son at college. I was thinking, 'my baby has grown up' and had a few tears in my eyes. When it was time for our youngest girl, the last of 3 children, to go to college, I was at the rejoicing point. We had succeeded!!! Three having graduated from high school and all going to college!!
After her 'orientation classes' I asked her how she liked them. She said that she didn't go, but partied at the frats instead. Now here's a girl who wouldn't date in HS and was a home body, and didn't drink. When classes started, she was ready to study, and in her soph. year she met her husband to be. She told him that she was going to study, and so was he. His grades came up!