To be honest I doubt those bulky humans in Kul Tiras will be an allied race. Most or at least a good chunk of the humans in Kul Tiras seem to be normal and share the already existing human male model. Imo adding the monster hunter humans as an allied race would be like adding dire trolls or orcs as one.
I'd either put my money on vrykul. The events were set up in Legion with Sylvanas trying to enslave Eyir, which would easily make the Horde less favorable. Most of the allied races also seem to join their respective factions due to a cultural connection with an already present race.
While Northrend vrykul dislike humans, the Tideskorn have been shown the repeated strength of humans and Sigryn, current God-Queen of the Tideskorn was partially put into power by Dalaran, so she would undoubtedly have respect towards them.
The vrykul would also have a respectful outlook on the dwarves and gnomes as well, considering they all have a titanforge background.