Here are the new skill levels for doom 1 and doom 2. Created with the help of: ZDoom forums and Slade.
Just load up the file with and ZDoom compatible sourceport and.... "enjoy"???
Here's the details about the skill levels:
Super Easy - "baby mode" keys are visible on the automap, monsters have less health and you get more ammo.
Easy - Your typical easy mode. keys are no longer visible on the automap.
Normal - It's just a generic normal mode.
Hard - You get less ammo, the monsters have more health and they are more aggressive.
Very Hard, Unfair and Impossible - Find out for yourself.