A bit late with my reply but it was on the same page you posted your list
https://www.mmo-champion.com/threads...1#post48536172
NExt bit is helping you a bit with possible reasons. (more by bringing up story conditions really
)
Elite forsaken probably clash more with Death knights who lore wise have humans as core. So elite undead look just like alliance human DK's :P. Lorewise it makes sense they look the same, the excistance of elite forsaken is extremely rare though as they have to be powerful individuals as they died or had extra juice put into them on the original resurrection for reasons. But that story element fits the adventurer perfectly.
I'm afraid that allied races always need to mean being a big part of the faction instead of just being friends where adventurers of that race just flock to a faction.
Hozen remains iffy, its probably better to do another race which horde has better selection of. But the story element for it would be they gained some weaker blessing of what the Monkey King partly got. (the monkey king is immortal or atleast lives longer). This however could also lead to them being alliance just like the monkey king is more alligned with the Alliance.
Their is already lore about Orcs possibly becoming 'Dragonman', Their called Dragonid. You saw them in Blackwing Lair during vanilla and TBC where you saw orcs shapeshift into Dragonids. (Dragonids are those bipedal dragons that are two handing a doublesided spead and twirling it).
Their is a chance that the Dragonids shapeshift into orcs but i believe they actually were orcs originally. Especially in TBC.