Oh, forgot to add:
I'm aying this, needs some work, needs some magic, but it's a very good base.
Well my first thought is that there's a lot of monsters from the start - by the Doom1 standards of course. It gets better in this "departament" tho, but there are very minor things that sometimes make a fight unnecessarily hard (almost no way to get past the baron, unless you attack him from the other side).
One thing I would definitely change tho - remove most of the imps on ledges, because original Pandemonium instantly comes to mind, and we should avoid this.
Foodles says he doesn't really consider this map to be "complete", and it lacked something to me as well. Can't grasp what exactly, but I'd recommend modifying it before inclusion.