My mods always include

• auto input switch (qol when playing on an ergonomic Xbox controller on the PC)
• cutting room floor (increases some content based on unused assets in the base game and the mod author's arbitrary judgement)
• convenient horses (makes horses nicer and this plays nice with other relationship mods)
• nethers follower framework (allows 20 followers at once and can configure follower outfits and can have followers loot for you)
• unofficial Skyrim se patch (mod author made changes that make Skyrim a little less buggy based on how the quests seem to make you think they work)
• unofficial ae Skyrim patch (arbitrary tweaks by the mod author to make ae less buggy)
• SkyUI (user interface that is more efficient than the base game and adds a menu to the start menu called "mod configuration manager aka mcm" and it allows you to configure any compatible and configurable mod.)

You can build off of that in a lot of ways. There is also a nemesis engine that is better than FNIS (allows true directional movement, some combat mods and new npc idles)

You can also get some weather mods that change the feel of the game.

You can also get some lighting and shadow shading mods.

You can also get some content expansions (serana dialogue overhaul, wyrmstooth, falskaar)

There are also some mesh improvement mods (high poly, smim, etc.) To make the walls and floor less jagged.

If you want to change context, you could get one of the "alternative start mods"

Mods are less to do with your level as a player, more to do with how you want to change the game? I.e. Do you want it to be more balanced, do you want a better and more immersive RPG experience, do you want combat and gameplay like Assassin's Creed or Sekiro or Elden Ring, do you want it to be slightly more sexualised or a fully featured adult / sex modded game, do you want next gen graphics, do you want bugfixes and quality of life stuff, etc etc.

So what would you like, as a starting point?

There are some great base-install modlists for both the Vortex (via Nexus Collections) and for Wabbajack (a more fully-featured modlist installer). These modlists will cover the major bug fixes plus the frameworks or extensions used by many other mods.

One modlist for each tool covering what essentials if you want to move on and install some other fun mods of your choice on top:

• Truly Essentials for AE 1.6.640- Nexus.
• Skyrim Modding Essentials - Wabbajack.

If you're modding with Mod Organizer 2, use Wabbajack to install a modlist. If you're using Vortex, install a Nexus collection with it.