Im not really good at explaining stuffs so I apologise if I messed up my explanation:
Idea for SK: Fusion Recipe
Basically a recipe that requires stuffs like Alchemy Orbs, materials & crowns but it requires 2 or more equipments to create a new equipment.

e.g.:
Recipe for Firestorm Edge
Materials:
5 Blue Shard
5 Red Shard
3 Scrap Metal
2 Gel Drop
2 Gel Core
1 Static Clinger
1 Torchstone
3 Advanced Orb of Alchemy

Weapons:
Shocking Edge lvl 1+
Searing Edge lvl 1+

Benefits that I can think: Fusion recipes are useful when introducing new equipments.
I hope this idea gets into SK :)

BTW, fusion result does not necessarily have to be like 1 + 1 = 2 cuz it'll be like too OP if stats are like 1 + 1 = 2 (-_-)