I don't know if this has always been the case, or if it was just recently, but I'm noticing that BM is getting faster paced when my Ursoc trinket procs/ when Hero is up.
Survival also feels faster paced when spamming Mongoose Bite.
MM doesn't feel much different since you cast shots most of the time.
The GCD for Hunters got changed from 1s to 1.5s in Legion (god knows why they think 1.5s is fun), which means it now benefits from haste again. It didn't previously (besides pre-cata, before they made it 1sec GCD)