Anything like Immoral Conduct

Anyone remember Cory Whittle's Immoral Conduct for Edge? Are there any similar wads that enhance normal Doom gameplay in a similar vein but for other engines (such as Zdoom, Skulltag, etc?)

Nope. It's never been done again since that wad.

If all you're looking for is gameplay enhancement mods, you could try Psychic or Zero Tolerance both of which are for ZDoom.

You might be interested in Don's Challenge, also by Cory Whittle, but good luck finding it.