I've never played this comp but i'll try and figure out somewhat how it would go if i were to play it
in terms of CC you've probably already figured out that you have enough control to go on anything you want. Both you and the boomkin are hybrid healers, so it should be fairly annoying/difficult (depending on how you play it) for the enemy team to get one of you down.
We'll continue the strategy that you originally wanted to do which was kill healers and that is more than possible with your setup in mind. how you open inst really the most important part of your comps's strategy unless you were planning an all in K.O aka burst someone down. you can and should be able to just spread aids with dots and live through there opener, assuming this is an RMD for example, once you've survived there opener and gotten through the kidney's and icy nova's you should be ready with your orbs, or near close, as you mentioned previously you said you followed up your fear + arcane torrent onto the healer. Try instead to work with your druid and Co-ordinate a cross CC onto both mage + rogue if possible. Do not use any of your cc such as HOJ + bash + physic horror unless you really need to survive there opener/killing spree and such
Landing the kill and switches
i used RMD as an example but the way im laying it out can pretty much be transferred against other comps in some kind of familiar variation (in terms of settings up your damage and CC). Most of your kills/forcing big cooldowns should lye with bashing the healer with a root beam on top and going with everything you have, followed by your physic horror as you want to keep him in that beam for aslong as possible, and your silence thereafter ,forcing HOPEFULLY trinkets, NS, skin, anything, once you've forced enough that you're happy with the progression of the game the enemy DPS are no doubt out of CC / already trinketed to peel you off, and you're back to offhealing, staying alive and dotting shit again, your druid also has the option of cloning the healer once you've done all of your damage to prevent him from healing himself to full, and hopefully in that clone you can make some other CC off it that isnt needed for the kill switch onto the healer which can also open up oppertunities for killing the DPS also (due to your spread dot damage previously before the switch)
Make sure you are co-coordinating with each other when you're both able to do damage and setup the CC correctly, as if you udont have orbs, and he has starsurge procs and you waste CC and damage on what could of potentially been a kill, all that has been wasted and you'll no doubt fall behind and lose.
on top of all this, your comp doesn't really have a name its just a spell cleave of some kind, maybe someone else can correct me on that. AND your comp doesnt really fit anywhere in the meta if you're planning on pushing anything past 2200+ if you're looking to climb like a scumbag than mess around with your comp i'd suggest replacing the boomkin with a frost mage and blizzard will give you a free glad title
Best of luck to you