Disclaimer: those are mods that I especially liked this past month and that found a permanent spot on my modlists. I do not claim they are the best mods, nor do I imply others are not good. I am in fact enjoying many other mods not listed here.

DragonDoor by Archimag

An alternative to Pursuit Enhanced the older classic and Pursuit Revisited.
Pursuit Enhanced took advantage of MWSE but not Lua.
Pursuit Revisited uses Lua but also comes with a bunch of features (lock doors, teleportation/transport restrictions in combat, guard behaviour...)
All three mods will make (smart) enemies follow you through doors.

Hard Save by Archimag

Continuing with his 'Morrowind is a Deadly Place' mod suite, Archimag gives us Hard Save where you cannot save the game while in combat. If you like this kind of punishment, also check out Merlord's No Combat Menu mod.

Beauty Scrolls by Archimag

Archimag has been super busy with his NM4 series (making my game deadlier than ever) but he also found the time to make a mod to prettify inventories! I like pretty as much as I like deadly.

qqqbbb's Cheat menu is an invaluable tool to cheat, but mostly to test mods.

Ald-ruhn X pathgrid by Malic

A couple of months ago, we got Ald-ruhn X by Pinsvinnn and I loved it. The only issue were pathgrids. No more. Thanks Malic!

Splash Resource Pack by NZdawghaus

While not technically a mod or new, I added this nice modders' resources because I've used it and enjoyed it (I think it was originally on Planet Elder Scrolls). You will find backgrounds and logos for Morrowind, Tribunal and Bloodmoon. You might also like his Icon Replacement Pack: I find them super useful especially if like me, you have multiple installs of Morrowind.

Better Enchantments by Aracelliy

A mod that overhauls enchantments, making some of them constant, but doesn't make me feel like I am cheating. Win.

Honourable mentions

Blood Magic by Hale

I like the concept a lot and the implementeation is the best that can be achieved without fancy scripts. Because mods have spoiled me rotten, I would love to see this with Lua capabilities, might also work with the excellent Magicka Expanded framework. Hint, hint.

A collection of small mods from Zelazko

Zelazko has made small but nice modifications to a few Fighters Guild Quests that give you more options to complete said quests. Eventually, I'd love to see these small mods merged into a single "Fighters Guild Quest Choice" mod.

Museum Quest Finisher by Necrolesian

If you are annoyed with quests that still show in your journal even after you supposedly completed them, grab this. One less quest that stays active.

The Role They Were To Play by PoodleSandwich

I've started the game so many times that, to my great shame, I skip the intro so this mod is lost on me. It is still a valuable addition to the game. If gender incorrectness (prolly a word I just made up) annoys you, PoodleSandwish links to a number of mods that fix that in his mod description.

Eclipse of The Crescent Blade by Gavrilo93

A small mod that make the game more lore-correct: the blade is supposed to be illegal, and now, the guards know it.