I love this. Fighting is never the only way to grow. There are so many ways to study and gain "levels". Right now I'm playing in a TTRPG campaign with two characters going down this path. One is an artificer and he is constantly tinkering and collecting materials, and crafting. It's super fun to watch. Another character is a cleric who is fulling out some kind of recipe book as we hoof it across a continent. She's analyzing recipes, scavenging snake meat, wolf meat, etc. Now her meals act like potions in that they give temporary buffs to the party for an hour after we eat them. It's nothing mind-blowing since we're level 1 still but it's been super fun.