I would delete Blessings and make them changeable against Odin Marks. Instead of that granting a 2. Legendary Item Slot and make those items be upgradeable with Odin marks.
Uru Items should get deleted and Runewords should be put on Legendary Items. Also Runewords should become more powerwful.
Relics should get deleted and be changeable against Omega Points. Or there should be a a Relic Cube where you can put in 4 different Relics with higher stack.
Rings should get deleted. Only Ring that makes sense is the one from Lord of Rings or Green Lantern. Cosmic Rings could be changable against unstable molecules.
Medallions should get deleted. Players can change their Cosmic Medallions against Boss Specific Artefacts.
Insignias should get deleted or be changed into only Team Insignias granting only Special Teambuffs. Cosmic Insignias could be changeable against unstable molecules.