If you were to fully explore the game but not farm any respawns, what level would your party reach?

depends heavily on your party the amount of mastery they can have in learning and the amount of points you choose to invest in the skill I guess.

if I had to guess I'd say around level 80, of course it still depends on when you actually get your master learning but that's a good ballpark

I am usually around level 95, but I'm not a total completionist.

I do (and clear) all dungeons and kill a bit of enemies outside.

If you were to be a completionist I would guess that you would end up at around level 120-130.

The only respawn I do are some fire archers, New Sorpigal, and drakes that spawn from the well in Kriegspire.
I do buy points in Kriegspire.
I clear all maps.
I would guess my average would be 90-95.

So 80-85 sounds right

Thanks, everybody.

According to my notes, my party trained to level 100 with the Hive itself yet to be done, and some titans remaining on the Hermit's Isle mainland, but everything else cleared out (including the Super-Goober area of the Control Center). This was with expert learning from level 6, master learning from level 20, but no learning-boost hirelings.

That sounds more right than the 80 figures mentioned by others.

Reloaded my last save game.

Master Learning + Teacher and Instructor, I reached 100 level by end of game. All quests done. Didn't farm any respawns, but did encounter them if a quest directed me back to an area already cleared.

Good to hear. I was doubting whether I'd get enough skill points to do what I wanted with the group, but looks like it should be ok if I prioritize very carefully.

I have a feeling Learning is not worth the skill points. You end up spending more skills points than you gain from the extra levels.

It's the most useless skill in HoMM3 for this reason. And there, it also takes up a limited skill slot.

Looks like that's the case in MM6 too. Ditto with the Learning NPCs.

Early game it's not worth it, but lategame it's insanely powerful. You spend 27 skill points to get master learning which gives a 30% xp bonus.

At lvl 40-49 you get 9 skill points per lvl.
At lvl 90-99 you get 14 skill points per lvl.

Do you really think that master learning nets you less than 2-3 levels late game with a 30% xp bonus which you can have for the entire game?

Edit:
Skill lvl 1 learning gives a permanent 10% xp bonus for a few hundred gold pieces. The skill is hardly useless.