Together with a guy I met on creator discord we’ve come up with an actually interesting upgrade/quest path, a new Melk that everyone will love:
Melk was supposed to be our long term “earn the weapon you want” overarching progress.
He’s not. So let’s first mentally discard everything that Melk currently does and then imagine the following:
Through Melk (in whatever shape or form) you get access to high rated white weapons.
with Melks help you can upgrade these weapons to the next rarity through mission overarching quests (with no time limit). “Use this weapon to slay 10 monstrosities” (not last hit based, duh) for example.
you can repeatedly choose new quests until the weapon has reached its highest tier, each choice will lock in one of four crafting options until you have a custom made weapon that grew along your experience.
once you have finished your weapon, it’s time to earn the next grey base and explore playing with it and crafting it!
I also though about how Melk can help with progression, but I had a much simpler idea:
Make weekly missions not depend on RNG with map-specific tasks (there are many threads about this)
Add “add item rating” option there where you can add like 5-10 rating points for 1000 Melk Bucks
Scale crafting materials per difficulty level much more aggressively where you have a real incentive to play higher difficulties to get more crafting mats. So, low diff = barely any mats on the map while high diff = much more crafting mats.
This way, you still want better base rating items from the base shop, so there is still incentive to check out that store, but you know that eventually, you will be able to upgrade your weapon just by playing the game.
Your suggestion also works and adds the “use weapon X to improve it” mechanic that is interesting, but I’m afraid it is too complex to implement for the current state of the game.