I dont know about you guys, i play mc side, my main char for now is reaper, and i gotta tell you this talent is not broken in pvp atleast, remember they only get -55% dmg reduced only when their hp drops to 30%, which means if they are at 31% hp, me and many other good pvp chars can literally 1 shot them, especially reapers, devs always told us that thia game is not about 1v1 its a group fight, every class has its owm counter. Just like how seekers remove warlocks from exictance in 4 seconds, reapers can remove seeker from exictance in 2 sec.
Drop seekee hp to 20% and even rogue with talent will be able to easily kill it, because of crits. Seekers are not much of threat in gvgs, because they dont have any long distance skill like rogue and they also dont have resistance skill, so all they do is just get permanent stunned to death, and if they do resistance build they will be too soft and easy to kill, as for arena like i said every class has its own counter. See stupid seeker in arena? Bring a good reaper with you and you will win. In my opinion devs are doing their best for both sides, and ppl keep complaining no matter what they do xd