The diference of note is that one fights as melee, the other ranged.
That's it. Any story or theme that the DH can explore, any issue that can be addressed...can be done just as well with Warlocks.
Everything Blizzard does annoys some group of players. Every expansion, every class development, every spell tweak upsets someone.
And between a class which doesn't exist and has zero players and a class which exists and is actively played...which do you think Blizzard will support.
Blizzards made this one VERY clear. In any contest between an existing class and a proposed class...the existing class wins. No ifs, ands, buts or debates.
Fortunately, Blizzard doesn't run the game based solely on forum complaints. They do what they believe is good for the game. If a point comes where adding a DH class will be good for the story, for balance or functionality, or just for sales, it'll happen.
Yes...and it'll be done in such a way that existing players won't be compromised.
Blizzard will NOT annoy Warlocks or any other class simply to bring in Demon Hunters.
That's a given.
Blizzard has already stated some of the issues and reasons affecting Demon Hunters as a standalone class.
Blizzard has already broken the class up and given out its looks and abilities to other existing classes. Something it would NEVER do if there was even a small chance DHs were planned.
Blizzard isn't going to spend a class slot on a class whose theme, concept and design space is already in game.
Blizzard isn't going to add a class which adds nothing of value to the game and, by virtue of its overlap with other classes, would actively hurt it.
Blizzard isn't going to annoy existing Warlock players simply to appease proponents of a non existing class. Blizzard therefore is not going to undo seven years of class design which has torn the DH apart.
What you have after you get rid of the Demon theme is a Dual wielding AGI based class which uses Shadow and Fire magic to augment its attacks and whose class name of Demon Hunter is, at best, antiquated.
And we already have the Monk and Rogue for that. If you add the Demon theme back in...you have a melee focussed Warlock. Which we already have as well.
There is no way to add in a DH class as it stands. And no way to redesign it to get around these constraints - constraints Blizzard themselves have noted and mentioned. Sure...Blizzard can always choose to ignore those constraints should it feel the need to do so - be it for balancing or gameplay or design or dollars reasons. But, in that situation, it doesn't need to. It already has the option available to it to implement a DH and still work within the constraints it has set, a way to do so without upsetting existing players.
Develop the DH as a Warlocks 4th spec. Develop their lore to state that DHs are simply how Warlockism developed amongst the Night Elfs, with its own set of rituals and customs. Allow NElfs to be Warlocks and bring in NElf Demon Hunters as trainers.
That path is technically feasible, doesn't break any lore and improves the Warlock class without upsetting players
EJL