The ShiftstonedEternal Power Calculator is a deck-building tool that visualizes your odds of drawing enough Influence and Power based specifically on the cards found in your deck.
Oathbreaker is bad in this deck. Less than half your units lifesteal, you have 8 other five-drops already, and JJSS messes up your influence requirements.
My tweaks:
-4 Oathbreaker
-1 Knight Chancellor Siraf
-1 Seat of Progress
-1 Seat of Vengeance
+1 Mask of Torment
+1 Blistering Wasp
+1 Katra, the Devoted
+2 Vara's Favor
+1 Seat of Mystery
+1 Xenan Banner
I don't agree with cutting a Siraf but yeah, Oathbreaker has underperformed. Going to fiddle with the list, I might just test out your changes and see how it feels.
My tweaks:
-4 Oathbreaker
-1 Knight Chancellor Siraf
-1 Seat of Progress
-1 Seat of Vengeance
+1 Mask of Torment
+1 Blistering Wasp
+1 Katra, the Devoted
+2 Vara's Favor
+1 Seat of Mystery
+1 Xenan Banner