To anybody who boxes affliction warlocks

I've been trying to make a high dps castsequence macro for my affliction warlocks. This is mostly for raid bosses for substained dps, not quite as good on trash. I have a good start but wanted to see if anybody had any good ideas on how to improve it.

/assist focus

/stopmacro [channeling]

/castsequence reset=combat/target haunt, unstable affliction, curse of agony, siphon life, immolate, life tap, drain life, haunt, unstable affliction, shadow bolt, shadow bolt, immolate, shadow bolt, life tap

With this macro I start out by casting corruption, haunt and drain life renew the corruption due to everlasting affliction so you should only have to cast it once.

Positives with this macro I was holding around 1100 dps with 3 of my locks, and around 1000dps with the 4th because he was casting curse of the elements in place of curse of agony. If you spam the macro it constantly keeps haunt, corruption, shadow embrace and unstable affliction. With the build in life taps it's extremely mana efficient while staying above 80 percent health, can easily spam for 3 minutes solid on a level 70 mob holding above 1000dps, still had around 2k mana on each lock at the end. My locks have 919 spelldamage each with fel armor up and a 56/0/5 spec.

Negatives about the macro, there are about 5 seconds for eacy full cycle where curse of agony isn't ticking, and the second immolate has about 2 seconds left to tick before the first immolate hits. Also if you can't constantly spam the macro you might have to renew the corruption. The drain life in the macro is there mostly to buy time, since the 255 character limit is in place, if you replaced with 2 shadow bolts your dps would be higher and i don't believe it would screw up the timing on the macro. Also due to the character limit you can't bind in trinkets, have to manually trigger them. Anyway, let me know if any of you have any comments/suggestions/questions.

First off, i almost never use castsequence. it limits me too much. what happens when a spell is resisted? what happens if a spell finishes its duration and needs a re-cast?
granted, i have an N52 and my buttons are mapped to my liking, but even if i was using a keyboard, i'd still try to NOT use a castsequence.

with that said... let me also add some of my ideas.
shorten the castsequence to Haunt, UA, CoA, Siphon Life, Corruption
i would put lifetap on its own button. you dont have dark pact?
i would put shadowbolt and immolate on the same button, not castsequence, but change with modifiers.
i would put drain life and drain soul on the same button, changable with modifiers.
even with the first cast sequence, i would want to split between the spells with cast times and the spells without. and even then... resists are a pain.

well this is just my opinion. i like to have way more flexibility than putting everything in one castsequence. there's no fun in that for me, especially when i need to change things up.

Yes, I have separate keybindings for each spell. I'm looking for something i can spam, that way i don't have to pay attention as much while i'm healing on my priest, I guess I didn't relay my purpose well enough... Yeah, i have dark pact, but i almost never use it, i find that haunt, siphon life and drain life give me more than enough health, i use life tap instead and still stay above 90 percent health, might as well let the pets keep the extra mana and do more dps.