I just use a cooldown count mod, ctra, location, and a tranqshot mod.
Here's one that most hunters like: Zhuntermod
I tried it a few times, and I enjoyed the fact that there were timers up for traps and also showed how long for aimed to be cast. But in the end I was just too used to playing w/o it so I don't use it.
I can't remember who wanted a tranqshot mod but here it is: SimpleTranqShot
Best tranqshot mod ever! This mod basically takes care of the yells/ra msgs when you fire your tranqshot or miss it. It beats the blizzard macro cause sometimes you still yell tranqed when you haven't, takes a couple seconds to yell missed. You can't shoot tranqs anymore unless there's a frenzy effect on your target.
Type /stranq to bring up the options and change the stuff around
%t = target's name
%p = your playerss name
Bosses so far that I know of that require tranqing are Magmadar (MC), Flamegor, Chromaggus (BWL), Princess Huhuura(AQ40)