Very cool Cherno,
Will you be expanding this mod to include the other levels, e.g. Workshops?
I was recently wondering myself whether it would be difficult to remake Chaos (or any classic isometric/overhead shooter) in GZDoom by doing it as 3rd person with the camera slightly elevated and behind, or even overhead perhaps with very high ceilings and an overhead viewpoint, that art by Antto Koponen certainly gives you food for thought.
Other games that transitioned well to Doom are Hocus Pocus and Castlevania for those who aren't too familiar -
https://forum.zdoom.org/viewtopic.php?t=45804 and
https://forum.zdoom.org/viewtopic.php?f=19&t=57800.
Anyway, keep up the good work!
:-)