Impact:
This is one of our most visually appealing abilities, but it rarely has use. This potency of Impact is identical to Ver F/S while giving less overall white/black mana than either of the two. So in terms of priority, there is no reason to cast Impact if Ver F/S is available. Since it requires a Jolt cast to proc it while having a 30s duration, there is potential that it may never actually be cast. Depending on procs and white/black mana, the duration might expire before a Jolt/Impact cast would even be needed.

1 change-Make it an ability that is off the GCD, but reduce the proc chance from Jolt.
2nd change-Allow the duration of Impactful to be indefinite until the spell is cast. This change seems more boring though as it would literally be cycling the two skills.
3rd change-Have Impact casts grant extra potency and/or mana for the next Ver T/A. This would allow for priority over Ver F/S if active, but would not encourage Jolt casts while Ver F/S is active.