Have taken liberty with some of the other posted macros, and come up with this one.
It basically uses all my instant cast spells on one button, and I have my other casting spells - for now, on my action bar.
I have not really tested it yet though, since I am lacking pvp gear. I have used it without any issue in heroics - but heroics are garbage, so that’s not a real good test. But, at least it doesn’t lock up, and no one dies =)
/castsequence reset=0.3 0,0,0,Wild Growth
/castsequence reset=target Wild Mushroom
/castsequence reset=0.3 0,0,Swiftmend
/castsequence reset=1 0,Lifebloom,Rejuvenation,Swiftmend
/cast Nature's Swiftness
/use Wild Mushroom: Bloom