Let us say that Mortal Strike hits for 100,000, increased by the 35% modifier to 135,000 in PvP. After these changes it’ll hit for 155,000, which is ≈15% more than it does currently.
Unless I’m mistaken. 
I’m not…entirely sure? Why it wasn’t worded more like this.
Wish we had an optional toggle to show how much stronger or weaker abilities are in PvP.