"Essential" mods?

Hi, I'm looking into lesser-known mods but I'm having a hard time figuring out which ones are particularly noteworthy outside of the big ones (e.g. PQ, STOPX, Quaternion). What are some mods that you recommend that I look into? Quality doesn't matter in this instance, as long as it represents something important or made waves in the community at some point in time.

First of all, welcome back!

Aside from what you've listed, I've always enjoyed MBPU, and quite a few examples of STOPX's work are loosely inspired by MBPU.

GLC4 by NaCL - honestly, that series is challenging in a very fun way.

Evil Mini Mod takes a nice twist on MBG in a nicely balanced and open fashion. I had a lot of fun playing it when I used to speed run this game.

JX