How to scale newly buffed shield skills?

Was very excited to try the newly buffed shield skills w the flat damage per 15 armor on shield. However, it really seems like it doesn’t add a huge amount of damage for me. I am a new player, and had heard flat damage is such a big deal because it gets multiplied by everything, but w shield builds, I just don’t see many multipliers available.

I was hoping nodes w “increased defenses from shield” would increase armor and thus dps, but they don’t seem to function like those. Any recommendations on how to scale this damage would be awesome ty!