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.
Loved GCD? Been using MADD leveller or MCC Leveler? Chances are you will like this: no level up screen, attributes improve with your skills AND you get to configure in-game. Praise Vivec, praise Lua, praise Mort!
Harder Merchants by Greatness7
Do you lose interest in the game after you hit your first million septims? Even using Harder Barter, you feel bad that your character picks up trading skills but traders never do? Problem solved, merchants haggle better as you level up, it's fair, you get better at your main skills, so do traders.
Illuminated Order 2.0 by Mort
Not a new mod, but one of my favourite quest mods, updated and fixed by Mort? Worth the download. This mod is perfect for characters who seek out knowledge, especially dark and forbidden knowledge.
Anchor Teleportation by OperatorJack
A new-old way to use the Mark and Recall spells. Anyone who's played Daggerfall will remember how it works. Simply put, every time you recall, your Mark is deleted. In Daggerfall, you'd use this primarily before entering a dungeon, and then again to get out. I know, maybe you were spoiled (like me) by multi-mark mods... Hear me out though: Magicka Expanded has teleportation spells to every settlement, so a flexible anchor is a nice new trick.
Smuggler's Run - Player Home by Corsair83
RFD's Splash Screens by Red Furry Demon
If you like your splash screens clean, good-looking and lore-friendly, this is for you. I am already a big fan of De-outlandered main menu and Daedric UI textures. If you are looking for different splash screens, lore-friendly and/or based on concept art, try Morrowind Screens Redone: lighter colour-scheme as well as notes; Concept Art Based Loading Screens and Fresco Splash Screens a minimalistic approach.
Smart Ammo by Abot
The QoL mod of the month: not only is ammo equipped automatically, you also have a hotkey to equip the ammo you manually selected. Oh, and it's esp-less.
Hardtrade by Archimag
With this mod, you will need to haggle more and you won't get as much for your items as you would in vanilla. The formula takes into account speechcraft, mercantile, personality, luck and disposition. A different approach from Harder Barter that scales the sale price down based on the item's value.