For me, the "many problems" of Beast Mastery can be summarized as below.
New Aspect of Cheetah: Horrible. Revert to old Aspect of Cheetah.
New Mend Pet: Horrible. Revert to old Mend Pet.
New Self Heal: Horrible. Revert to Animal Bond.
New Pet Survivability: Horrible. Revert.
New Utility: What utility? Took traps away, gave nothing. Took Camo away, gave nothing. Forced a choice between a sap and a stun. At least bring back Scatter Shot, FFS.