You have 4 covenants each of which has 2 major abilities that are completely different and unique and WITHIN EACH of those covenants there are 3 soulbinds that have an ENTIRE TREE of again relatively unique abilities (at least within the covenant) so we're talking about making a choice based on about TWELVE sub-trees and extra differences beyond those.
This should had been clearly simpler because I'm one of those idiots that have multiple degrees in the sciences and I still think this is not easy to wrap around your head for a coherent all around big picture decision.