New Ultimate Doom map I am working on.

http://www.filedropper.com/basenew

This map is for E4M1 and this will be a large map that has familiar elements of E1M1 coupled with a very large and challenging tech base. This map will be challenging but there is a lot of room to move and fight.

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-prn2/981005_470092906407957_819462393_o.jpg

https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-prn2/965171_470093043074610_1952526717_o.jpg

https://www.facebook.com/photo.php?fbid=470093306407917&set=pcb.470093593074555&type=1&theater

https://www.facebook.com/photo.php?fbid=470093463074568&set=pcb.470093593074555&type=1&theater

http://www.filedropper.com/base-tech

New version. many fixes and an exit added.

Your map has an interesting unusual visual style. I personally like how everything is dark, it creates a stronger atmosphere together with the music. The outdoor darkness combined with E4 sky works excellent.

I would reproach you one major fault, and that is the map is unintuitive. One thing is that it is generally easy to fail to notice doors, as that many of them are simply merged in walls without any seems, or are just non-obvious dark holes. I would make them "sunken" into walls 8 or 16 units, and light up a bit. Another thing, and more important, is that you often press a switch and have no idea what happened, and later you find that some door on the exact opposite side of the map have opened. This isn't very good. I'd recommend to use keycards instead of switches, or to mark switches and doors by colors or anyhow, so the player can distinguish where did the switched action take effect. I, for example, found all secrets, but didn't find any way to open this door.

Although your monster placement is done more than well, I think you still need to learn making proper ammo / item placement. Player is often thrown in situation where he has to fight lots of imps/cacodemons/barons and don't find any ammo all along the way, and at the end of the corridor he loses all ammo and expects he'll be rewarded with some. And what he finds? Soulsphere and armor. And then he must punch his way back with fist only.
Every time you use monsters that don't drop ammo, provide some shell or rocket boxes near them. Your map generally lacks ammo. Most of the ammo you get from fallen sergeants. Placing some more bullets and rockets in would be nice, along with making the weapons easier to find by highlighting doors, as I already suggested.

The last thing I would mention as not ideal choice are the windows, which are impassable even though they're huge and almost not raised above the floor (only like 16 units, which the player normally can step up). I'd either raise them to 32 units above floor, or (less preferably) add some bars texture in them. In addition, you forgot to add impassable flag to this window.

And as the very last thing I found this visual bug near the start. (the LITE texture shouldn't be there)

Gameplay wise (by the means of a shooting fun) it was enjoyable map, except the moments where you run out of ammo in tight spaces. Running through (better said, around) dark forests isn't common in wads, and was an interesting experience in yours. And the thing I like about your wad is how you go through nearly absolute darkness for a long time without encountering anything, and then suddenly fireballs start to appear from everywhere - but the imps are still easy to deal with.

Wish you good luck with wadmaking ;)

http://www.securitronlinux.com/files/basenew.zip

This is a new version of the file with the doors highlighted and some useful gameplay fixes. I have added lights in the hallway either side of the doors. This lights them up very well indeed.

#EDIT.

Another version uploaded with a new area and the passable window fixed. And I uploaded the wrong file; so here is the proper one. A bit more ammunition added at the end of the long corridor and the new area with some more health at the start of the map. Now this base map is getting seriously large. But I do not want to do much more on this map. I just want to see if anyone is happy with this before I add this to /newstuff.

This is a newer version of this map with the entrance area bug fixed.

http://www.securitronlinux.com/files/basenew.zip

See what you think of this.