You're thinking of the Nebula armor as damage focused, which isn't really it's goal. The nebula is a great support armor set. Those buffs aren't meant for you, they're meant for your teammates. Specifically, you'd use the nebula armor while staying away from enemies, and other players would be the ones to approach the buffs, while assisted by your suppressing fire. By yourself, you can just not take it. Hell, by fighting the moon lord to make the armor, chances are you got the last prism, which means: you don't even need those buffs!