Just a bunch of my personal opinions on how to further balance out weapons and armors. This is more or less a huge idea dump, feel free to discuss or critique anything on the list.
Armor Sets
-Azure Guardian Set-
Add global CTR low to the 5* pieces.
-Almirian Crusader Set-
Add global CTR low to each piece.
-Heavenly Iron Set-
Change low sword damage bonus to global low damage bonus.
-Chaos Set-
Remove Normal defense, buff current bonuses to medium, add low ASI bonus.
-Wolver Set-
Remove status resists from the 2* through 4* set.
Swords
-Cold Iron Vanquisher-
Remove knockback from charge attack.
-Winmillion-
Add a 5* version.
-Hunting Blade-
Change damage to split Normal/Piercing.
-Riagdoon & Flamberge-
Increase chance to cause status.
-Cautery Sword-
Replace it with a poison-inflicting Normal damage Brandish line?
Guns
-Volcanic Pepperbox-
Increase range and fire chance, remove knockback from charge attack.
-Iron Slug-
Add a "good chance to cause strong Stun" (Callahan has moderate Stun)
Bombs
-Irontech Destroyer-
Remove walk speed penalty, increase radius to slightly less than Nitronome.
-Big Angry Bomb-
Increase radius to slightly less than Nitronome, add a Stun infliction on being hit by the bomb. Basically, it should be a bomb version of the new Sudaruska charge. :3
-Deconstructor-
Change to Elemental damage, add a 5* version.
-Ionized Salt Bomb-
Reduce charge time to equal Radiant Sun Shards.
-Dark Retribution-
Revert bullet speed nerf, keep the damage nerf.
Shields
-Omega Shell-
Add Poison resist.
-Aegis-
Add Shock resist. It'll balance it out with Heater's Freeze resist and we also don't have a piercing + shock shield.
Now I want to kamikaze run with that chaos and a swifstrike.
-But you're making cobalt and Almire exactly the same.
-Cold iron becomes totally superior to levi, but I guess you want that since calibur recipes are basically free with missions.