First up, absolutely love your work. I've been using your Summoner routine to gear it up to full i90 then threw it into T6 last night. Pulled some comparable DPS against playing my Monk and better than the two caster statics in our group haha.
Just a few things to comment on as I observed.
- It seems to have a habit of half casting Shadow Flare regularly before auto cancelling then takes a good few seconds to cast another spell. Is this just following some logic of pre casting Shadow Flare if needed then cancelling when it determines it's not needed? Between the auto cancel and the wait time (outside the mandatory global cooldown) for the next spell is a good 3-5 seconds lost on casting.
- I'll have to look more closely tonight to confirm this if I take it through T6 again but I'm pretty sure it was trying to Bane the boss in the centre of the room when the bulb mechanics were sprouting around the edges of the room. Maybe it could be possible to add a range option to Bane x enemies in y ylms?
- Lastly the seemingly forced Sustain heal for pets and self healing spam when either are below a certain amount of health. Unless I've missed an option somewhere this is only really for soloing since there are two dedicated healers that will likely overheal you anyway if you're pushing for more health - that and there's a mechanic in the fight that instant kills you if you're moving / casting which I died a few times to because the bot was self healing

So if it's possible to have options for these that would be fantastic.
Other than that, your Summoner rotation is pretty much perfect!
Edit: Just saw your above post on pausing ExCombatAssist with Shift+X. Although that fixes my last point in a way suggesting for more options are always good xD