I'd like a link to a list of (probably mostly quest like) mods sorted by ascending suggested minimum player level.
If such list does not exist, well, maybe someone will get the idea and do it

What if a large mod with several different quests and interiors has many different levels required for each?

Good question, probably 2 orderings would be best, one for low level/new game players, ordered by lowest level in range, e.g. for Mod2
Mod1 ( level 1-5)
Mod2 (Level 1-50)
Mod3 (Level 10-15)
Mod4 (Level 50-55)

And the same list ordered by max. suggested level more useful for high level players, e. g.
Mod1 ( level 1-5)
Mod3 (Level 10-15)
Mod2 (Level 1-50)
Mod4 (Level 50-55)

Sounds reasonable, but I still am a bit unsure as;
My mod will have bandit lairs for level 1-5, 5-10, 20-30 and 40+, similarily the quests will be increasingly difficult. This is so that a player will be finding a challenge at every level. So it is meant to give material to every level, or even for especially mages, warriors or thieves.

So if I am right my mod would need to show up at every level, and I believe most large expansions including new provinces will have a similar point. So i foresee your listings being well working with smaller mods, single dungeons or lets say an island somewhere, but expect trouble with mods that add a lot.

This said it is a very interesting compilation that can help you on the way.