...Ruby Dynamics is already a better AoE alternative to Rose of Destruction tho?

They both share a recast, so it's down to the content/role you're running, but in a straight comparison, Dynamics is doing more dps that Destruction on 2+ enemies. It's an AoE with no fall-off, and you don't get that many of those. Not really seeing how 30 extra potency really changes anything here.