The Culture: Your Character Improvement Rules Are Borked Because You Don't Think It Through

Levels, Skill Checks, XP totals. You do not comprehend what they mean to represent, WHAT THEY ARE ABSTRACTIONS OF!

These are all abstractions of what you really have to do to get better at anything: put in time doing specific work under expert guidance to achieve a specific benefit.

AD&D1e made this explicit in its Training Time Rule imposing this very cost upon a player's man when that player chooses for that man to gain a level in a Class. Classic Traveller also makes this explicit when it says that you have to bench your man for years to improve his skills.

Don't use abstactions when they are not necessary.

You can, and should, just impose a time and resource cost to make the Number go up or to remove a penalty inflicted as a consequence of play. Want to get better at cooking? Get training and put in work practicing. Want to get that limb fixed? Find a doctor, get the operation done, and spend months in rehab relearning how to live with it.

Suddenly you can't do the Get Along Gang chasing the ruby anymore, but that shit's Cargo Cult faggotry anyways so it's loss is a trivial cost.

"But you play AD&D"

And? Levels are an abstraction, specifically for the concept of that a man is a Hero or Leader Figure in wargame terms with sizable units, and only make sense under that paradigm- and AD&D is under that paradigm; you don't see that in TORG now, do you?

Could you make a Fantastic Adventure Game without any of the usual Number Go Up mechanics? Without anything more than "Spend (X) time and (Y) material costs"? Sure.

Maybe someone should show you how it's done.