The Inquisitors are something that are being unveiled with the Legion's full scale invasion as well as our own invasions and treks into the Legion's worlds. I don't know how common or how many encounters there might have been with them in the past. However, with the Nathrezim, I will say that it's probably one of the ones I would stay away from. Although, there is the argument that the Nathrezim are a race of demons and they quite clearly are not all on the same level of power as Tichondrius. So, if it is done well, described in the manner of it not being some uber-level demon, then it's feasible.
Felhound: The felhounds serve the Burning Legion as their devourers of magic, their forerunners, and torturers of spellcasters. An endless desire to devour magic is their greatest trait, especially when paired with their endless appetite for wickedness. Demon hunters who bind themselves to these creatures are no doubt the masters of defeating spellcasters, seeing their spell-weaving enemies as little more than fonts of power to draw from.
Things like Tauren melee reach being bigger, which is something I experienced going away live during Black Temple Illidan progression (at least for that particular encounter), is confusing to players as it's a significant advantage over other races in some instances. No quest tracking is another apparently confusing issue, as many Mankirk's WIfe seekers well know, and there's a whole lot more where that came from:
While the avenues for a blood elf to become a demon hunter are limited, that does not mean that the story for this character is limited, regardless of following a particular path. What did your character do prior to the destruction of Quel’thalas? What drove your character to believing in Illidan’s cause so much more than Kael’thas’ own during his defection? What did your character accomplish during their time serving under Illidan and Kael’thas throughout northern Lordaeron, Outland, and Northrend? What does your character think of their people in the wake of Kael’thas’ death?
I used Zygor for legion and BFA, used AA on an alt for BFA. Personally i like Zygors format more. I like being able to target things like achievements. I used Zygor to get my Mindworm and my Lucid Nightmare as well as finish the Rep grinds for the allied races. I have zero complaints. My experience was great. I also used Zygor for some professions, recipe acquisition, a couple mounts, all of the Suramar quest line. Thank God for that. And for the last zone of Draenor on my Demon Hunter.. i forget the name.. Whatever the big daily hub thing was called.