Good mods

Real men play vanilla only

Try Pirate Doom (partial total conversion, it's like both mapset and gameplay mod)
www.doomworld.com/idgames/levels/doom2/Ports/p-r/pirates

I will organize my recommendations into groups I guess trying to put myself into the shoes of an inexperienced doomer. These are in no particular order within each category, just whatever comes to mind at the moment. Obviously there are loads more but I am not going to write a book. Assumes UV difficulty.

Some easier map recommendations (easier than plutonia by a great deal):
1. Fava Beans
2. Coffee Break

Middle of the road (these wads are around Plutonia difficulty, may be harder, but don't venture too far off its difficulty for me to put them in the hard category):
1. Cydonia
2. Monuments of Mars
3. Earthless
4. Auger;Zenith

Hard wads (these wads will get your feet wet in the modern world of challenging maps):
1. Crumpets
2. Altitude and Mutabor (both similar maps by tourniquet, imo the de-facto standard for ambitious vanilla mapping)
3. Counter-Attack
4. Vanguard
5. Running Late 2

Very Hard wads (these wads are for people who know exactly how the mechanics of doom work and can *easily* deal with the above wads):
1. Sunlust
2. Miasma
3. Disciples of Darkness

Fringe difficulty (these wads are only recommended if you can beat all of the above saveless but maybe you just like hard stuff like me when I started out.. so here you go):
1. Sunder (I only really play maps 2, 3, 5, 7, 11, and 14 - the maps after 14 are what put this in fringe territory)
2. Abandon
3. Toilet of the Gods
4. Maps by this author: doomwiki.org/wiki/Death-Destiny (all maps are generally in very hard/fringe territory)
5. Maps by this author: doomwiki.org/wiki/TimeOfDeath (not all maps are fringe territory, things like rjsloth are very fringe, tod is still around on this forum so if you check out his stuff I am sure he would help you out)
6. Maps by this author: doomwiki.org/wiki/Zachary_Stephens_(Ribbiks) (later stuff is in fringe difficulty, earlier stuff, save for swtw not so much)

Extra wads list (these are wads which may be all over the place in difficulty but will provide a unique experience):
1. Emergent - random monster tp setups throughout the wad
2. The Given - pretty much the defacto puzzle oriented map


For mods I only really play two:
1. Complex Doom
2. High Noon Drifter

I guess it is because of how the monsters are presented and also based on the ironman for Miasma and Criticality. I remembered suitepee getting destroyed by both very early on.

yades This video might be helpful, its a good starting point if you're not sure what you're doing yet.

Essentially, once you've got your preferred source port installed, and your DOOM2.WAD file inside the source port folder, you can download .WAD files or .PK3 files, and just drag and drop them on top of the source port .exe (gzdoom.exe) and it will run the content.