I like your Poster, but I might suggest putting dark cloth on the walls you are close to as to avoid reflection off the walls from the enlarger light. It can cause a bit of fogging on the paper or a loss of local contrast in the image.

I'm adding an example...


See the first or 7th picture as an example of what I am talking about.

If you can't you will live without it, but I think that close to the corner you will see a difference.

Great start!