That looks great. I actually wanted to do a port of an id game in Rust for the longest time but never managed to find spare cycles.

I would add to the list of feature to tackle next:

- Convert from 320x200 aspect ratio to 320x240 aspect ratio. You can do that by converting from 320x200 to 1600x1200. This is easily done with x5/x6 which give you the same aspect ratio as 320x240 and you get no pixel selection artifacts.