Cheeky,
I downloaded your spreadsheet, great work, but i have some comments and questions.
It seems I'm missing Imp.HM in pet data.
Thing is I'm BM but leeching HM from MM hunter.
Maybe you could make extra tab: Target
* level - already done
* mob/boss - already done
* armor - already done
* debuffs (Imp.HM, CoS(arcane), Arms warrior 4% debuff, gift of arthas

, Hemo,...) - the hard work... but would imho be interesting insight on hunter synergy. I'm specially interested in question, what if target has dazed effect all the time (blade twisting, shield bash, concossive barrage...).
Tab: Equip compare
I know i can always change things in gear tab and compare. But socketing 3slot items 10x in row can be fun
Something like:
Item1 vs Item2
*agi
*ap
*hit
*crit
[top] Erap or dps, or change VS current gear.
I don't remember or i didn't saw. Agi
Crit = AP conversions with final gear/talents/rotation.
(something i find extremely useful in Lactoses sheet, that provides Item1 vs Item2 with next to 0 tinkering)
How do you model TBW in? I always fire TBW up with Rapid Fire / Trinkets(abacus/kiss) / Troll Zerking or Bloodlust. It results in more shots fired with +10% damage modifier, and also that means pet usually has far better focus regain at that time (doing more specials at 50% boost, in case of BL with greater speed also). I'm no math expert but seems logical to me that damage should be better this way instead of giving haste and tbw some static average % increase.