kill over time damage (bleeds ) and the spec will be fine (more or less ) . add the over time damage to main damage . the best skills of that spec have the biggest cool down so if you do that they will simple not unbalance the game.
that spec is viable for pve cuz you have time to see your bleed works . but in pvp its not viable cuz you are dead . i am saying that since second game beta .. but none hear me .
some people need to learn to play pvp ... use rotations . AND PLAY PVP WITH PVP ARMOR AND NOT PVE ARMOR ( i have see many times in warzone people with 0 expertise rating ... its only logical to die easy with that kind of armor.. or people saying about weak classes when they have the lower pvp armor and they are against people with elite war hero armors playing premade games and talking to ts3 .. ( it only natural to lose with these people they are organized , ask question for people that they know how to play, and get organized) .. well about the cheaters you cant do anything ! so i cant suggest you anything
have a nice game people !