If you are in arena, even as a healer you’ll probably be asked to do some CC.  While I’m not particularly good at arena, here are my two favorite CC related macros… 
This macro will cyclone my current target if clicked… or cyclone my focus target if shift clicked.

#showtooltip Cyclone
/cast [target=focus, modifier:shift] Cyclone; Cyclone
#showtooltip Cyclone
/cast [target=focus, [...]

Although I’ve recently replaced this with the Spark of Hope, I thought I’d share this macro I used with my Spirit-World Glass.
#showtooltip Wild Growth
/use Spirit-World Glass
/stopcasting
/cast  [target=Ashkore] Wild Growth
/script UIErrorsFrame:Clear() 
#showtooltip Wild Growth
/use Spirit-World Glass
/stopcasting
/cast  [target=Angela] Wild Growth
/script UIErrorsFrame:Clear() 
Basically this targets me, and casts Wild Growth.  If my Spirit World Glass CD is up, it casts that, if [...]