The second death, (ignore other wad with same name)

The Second Death
Custom map for DOOM II
*Please ignore other wad with same title! I made a mistake whilst uploading it, and can't figure out how to remove it! 
My first map for Doom 2. Hope you enjoy it, but either way, any feedback you could give me would be appreciated,
especially concerning the balancing and overall difficulty. 	
Tested in GZDOOM. UDMF format.
Map should be something of a medium difficulty, thought it's hard to tell, seeing as I already know all the 
surprises. 
First 3 difficulties have less enemies and more pickups than last 2.
Thanks for playing!