First off I'm not talking damage.... (though I would like to see the Tags get buffed from 25% charge bullet damage to 35%)
Both before and after the Gunner update still the biggest problem facing Catalyzer users is teammates killing your targets or placing excessive tags on the enemy.
So here's my fix to this problem. If an enemy dies with tags still on them these tags will attach to the nearest enemy in the room. If you kill an enemy with a catalyzer blast and there are tags that don't do damage to anything (blocks, target enemy, surrounding enemy, frozen teammates, etc) then these tags will also seek out and attach to nearby enemies. Tags will fade if there aren't any enemies to attach to though.
I think the Catalyzer is ok the way it is.