There are two primary changes that stick out in my mind that I believe would really make Survival Hunter and Marksmanship hunter more fun to play.
For Survival Hunter, make kill command be off the global cooldown.
For Marksmanship Hunter, remove the cooldown on aimed shot and increase the focus cost.
With this change to marksman, perhaps precise shots could instead reduce the cost of your next arcane shot or multishot by 100%, allowing the lion’s share of focus to go towards aimed shot.
Trueshot could simply reduce the focus cost of aimed shot.
Overall, this would be a very minor change, but I feel it would be a great tweak to make it feel better to play. Thematically it makes a lot of sense with their resource being focus, to spend your focus on aimed shot.
For survival, having kill command off the gcd would make the rotation flow better I think. Spells that have a chance to reset their own cooldown is fun when it’s a powerful spell, like avengers shield for instance. However, for your primary resource generator, specifically when talented into mongoose bite, it feels like pressing kill command is pulling you out of your burst window. It feels bad getting multiple resets if because you will inevitably cap your resource, which is wasteful of both the reset cooldown and the overflow of focus. Having kill command be off the gcd or at least trigger a half gcd would feel significantly better.