I think they just need to add subrace catergories to similar looking races. Blood elves and void elves should have a high elf subcategory. And so they can choose to identify as high elf for example.
Humans should be mixed.
Orcs should be mixed
Dranei should be mixed
Tauren should be mixed.
Trolls should be mixed
Dwarves should be mixed, add the wildhammer dwarf category.
Nightborne should have the undead night elf category, and maybe highborne looks. Felbourne and followers of elune looks too.
Night elfs can have an undead night elf category and highborne looks. Nightwarrior tatoos.
Humans can have the skinny bodytype, undead can have the human models with dk eyes and natural skin tone colors of “fresh undead” basically all the customization a human dk can use. So horde would get humans with the forsaken basically. Kultirans too as fogsail.
Forsaken can get leper gnome customization and all the undead dk looks of other races, which would be huge.
Trolls can eventually look forward to jungle troll looks, frost troll, and maybe another bodytype to choose from
Dwarves get to look forward to frost dwarves, metal dwarves, earthen/clay dwarves.
Tauren looks forward to feltotem, grimtotem, Yaungol and Taunka eventually.
Gnomes- Lepergnome customization, full mechanized robot looks.
Dranei- Another bodytype Broken options. Lightforged mixed looks.
Goblins - gilgoblins, hell goblins, lightning goblins, mudgoblins (all fictional except gilgoblins but more elemental goblins would be cool customization).