As pointed out in another thread BM mastery skill is very lack luster for lvling and endgame.
My idea is called "Wounding Shot".
Wounding Shot - Deal x% weapon damage plus y. Your pet senses a weakness in your foe and engages with new vigor increasing white damage by z% for 3 seconds. 10 second cool down costs 40 focus.
Tenacity = Your pet sees the weakness of his foe and it's next special does x% more threat.
Cunning = Your pet has learned to identify weakness and reduces melee/casting speed by x%.
Ferocity = Your pet smell blood and deals x% more damage on it's next two speacials.
For leveling I think this would be great by helping BM level by making sure a tanking pet keep aggro. In pvp this will help with utility (maybe a snare instead of reduced attack/cast speed) and in raiding it gives your pet another means of doing more damage while giving BM another shot to use. I figure it's damage could be close to ArcShot but the main difference in damage will come from the 3 seconds of increased white damage and specials while raiding with a ferocity. It gives each pet more distincive traits and lets hunders work with their pets more by making it a cool shot.
Just my two cents. If you can post this on the suggestion forums if you like it please do. I'd like to see BM actually worth playing again with something fun.
Flame on.