Hej I will keep it short, long time Vengance player here doing low high level keys
Center Line - Keep this about demon spikes and meta buffs with side paths of resource generation, for example middle left is about creating orbs, center right is about Fury.
Left line - all about Frality playstle with spirit bomb buffs and early in the tree Fel Dev options (so right lane can also get some fel buffs)
Right line - immolation aura buffs for duration at the start and damage reduction, into soul cleave buffs and Fiery Brand buffs.
Here you would have different playstyle options.
Final capstones look good
Spirit Bomb damage needs buffing, its almost the same as soul cleave and I think when managing a second resource it needs to be a bit stronger.