Not having a silence anymore greatly hinders your ability to take down healers. What you do have, however, is stuns and fears and the like. I have pretty much given up on Avatar, its nice if you have a pally for hand of freedom but just 1 on 1 you will get rooted or something so pfft. I use storm bolt now and in conjunction with shockwave, that applies a pretty stable stun. Things you can also do is disarm- greatly reduces healing, you can fear to buy you time to get your stuns off cool down. you can hamstring to slow them down or just glyph crippling blow. You just have to stay on them and time your cool downs correct and force them to use powerful defensive cooldowns, once those are used burst em down. Be ready to shattering throw. Id also pool your rage up for a bit and then unleash it all in bursts because it forces them to have an emergency response.