Passives are one thing, since they should theoretically be complimenting the things upstream, but Blitz abilities, Combat Abilities, and Auras shouldn’t be vertically mutually exclusive.
For example, Psyker is not able to take the Prescience Aura and Venting Shriek Combat Ability. They simply can’t move horizontally across the tree fast enough. Similarly, Ogryn can’t take Point Blank Barrage and Bonebreaker’s Aura.
I don’t really see a balance reason for this to be the case either. I don’t think Venting Shriek and crit have any particular synergy and Telekinetic Shield is plenty strong, so it’s not a huge deal to give it up. It seems like a weird restriction.