Please consider the following:
These reactive abilities as they are now, are the only possibility for the warrior to obtain real burst damage.
If you put these on a separate GCD and take the damage from the Interrupts, the Warrior can now only drive a PVE-constant line of outgoing damage, which makes his attacks very much easier to be healed against.
I am rank 7 at the moment and i have tested a variety of Soultree-combinations in PvP, i have the optimal runes on my PvP gear and the r6 2h weapon, and with that setup i have trouble getting some other classes with certain trees down at all (no matter which soul trees / macros i use) in a 1:1 duel-like situation.
There is a variety of classes that can heal themselves, of course.
There are also a lot of mage & cleric builds (duracell-builds or the like) that heal themselves while having a considerable damage output. High-ranked players of these mentioned trees end up leaving the battleground having a very much higher damage output than a warrior of their ranks (they might be doing aoe damage instead of single-target, but still) plus a massive amount of heal-output.
Standing next to these players without beeing stunned, feared or squirrelled, constantly beeing allowed to deal damage on those, may result in them not loosing a considerable amount of health, while they are still group healing (if their team-members would be around) AND dealing damage.
As it was now, this can be very hard to beat anyways.
Taking all these extra slashes from the warrior (Interrupts AND all reactive) and limiting him to do only one of these every 1.5s, is a huge warrior damage drain for the PvP.
You end up beeing only abled to drive a more or less constant damage output line that will be expected, easily healed against.
If some of these mage/cleric builds who heal themselves AND deal damage AND regenerate mana at the same time are hard to get down at all NOW, how is this supposed to feel after the patch with these changes and roughly 5 ability attacks for burst damage less?