3rd Party Alternative Magic Item Creation Systems?

[Mir]

Looking for recommendations for 3rd party systems for magic item creation. Specifically I'm looking for systems that:

allow for gradual work on items while adventuring.

address ways to upgrade/add abilities to items.

have systems for disenchanting items and using that magic for other things. (4th Ed has resdium and I'd like to see alternate systems that achieve similar things in different ways)

include commentary on impact of magic item creation on the economy.

[Little Red Goblin Games]

We had a mundane weapon modification system in our book War Journal (and expanded in our Necropunk setting) that mimics the effects of magic items with a attribute/detriment system.

[Mir]

Wow, I'm surprised there is nothing else. I'll look at the reviews and things for the War Journal and Necropunk.