Make it easier to complete item sets.

[AkimboBalloon]

Artifact item sets are a cool mechanic, but currently most of them can only really be used if you also use the item vault.

I suggest that the probability of an artifact being dropped be increased if the character also has part of the same set, so you're more likely to find the Dagger of the Past if you have the Sword of Potential Futures already.

[astralInferno]

I agree with this.

[Frumple]

Wouldn't mind it. Half makes me wonder if some kind of like-calls-to-like mechanic couldn't be put in. Whatever kit you're wearing influencing what sorts you find, something along those lines. Not terribly strongly, but enough it's noticeable.