“It’s probably Matt Mercer’s fault.”
No leveling. you are Conan, you don’t start level 1.
I very much agree that it should be a flat power curve. No "levels", but slowly increasing abilities/talents/etc.
The weird phenomena in level-based RPGs, where at level 1 you stand no chance against a level 3 monster, but then when you're level 5 it stands no chance against you, seems inappropriate to the Conan setting.
The other thing it would need is a combat system with an action economy that doesn't favor the side with greater numbers as dramatically as, say, D&D.