It’s going to sound silly, but the first mod, and most aesthetically necessary for me, is one that fixes Kaiden’s stupid, melted Lego hair. I can not stand that melted lump of plastic on his head. I only started pc gaming a year ago, and a mod to fix his stupid hair was the first mod for any game that I ever downloaded.
The other mods I consider essential are the ones that cut out the mini games (I can do the stripped down Simon game on ME1 on console, but cylindrical space frogger was beyond me) and the one that lets you scan all the planets in 2 with one probe. That one is a legit lifesaver, since I have something called Ehlers-Danlos Syndrome. It made all my joints really weak and prone to sprains, and holding the trigger down to scan got painful quickly and I’d often have to stop gaming because I could feel my finger about to go. That mod means far less strain on my fingers.
Another good mod I like is the one that revamps the dreams in 3. Stone of the revamped dreams are a bit meh, but I just got to the last one before Priority Earth, and it really hit me.