Here is a DOOM WAD file that I build (well, most borrowed) of my own for Deathmatch II rules, which has the following merits that I think are must-have for a Deathmatch WAD.

• No big weapons. This is most important. Otherwise, if we get killed too easily, there'll be no pleasure in fighting.
• If there are big weapons, there should be some compensate in getting them, making it more equal to fight them with less powered weapons. The compensate should be either lose in blood or easy get suicide, plus easily get killed when trying to get them.
• There should be no corner that makes it easier to shoot than to be shot.
• There should be no big monsters that can't be killed within 3 Shotguns.
• It is safer when first regenerated, and you can get a Shotgun soon. Otherwise, it is more likely that you are hunt down to death even before you pick up a gun to fight.
• The WAD should not be too big / complicated, with many separated dead-end rooms. The official Deathmatch WAD is just this kind. When it is safer to hide that hunt, who will hunt any more and what's interesting when everyone is hiding?
• I think a good WAD is not a one that is full of tricks, but designed carefully for fight. I think a good WAD is an "equal" one:
• It is equal that you've just regenerated or have live for a while.
• The monsters haven't much power that you.
• It is equal for people to hide or hunt.
• It is equal to get or not to get a "big" weapon.
• I think the most interesting thing in playing the DOOM is the art of fight, the pleasure of react in a much short time, not just kill or be killed.