"they are from draenor so their form should be from draenor" its too much simple/naive and ignores that the druid, at least the four specializations, take the form of an already existing spirit animal or wild god/Loa, thats why everyone but the zandalari turns into a bear and a cat, because they assume the form of shirvalah, ashmane or ursoc, while the zandalari take the form of the dino loas.
Lions were also, not part of the guilnean terrain neither their culture, nor bears to be honest, and they turn in the same cat and bear aspect, because of the same wild gods;
Draenor was not know for their wild gods, while people speculate that rukmar and the others like anzu are ones, only Goldrin is someone mentioned in Draenor folklore by orcs, so they would need to take the quirks of the races they learn from, trolls and druids, therefore, they would assume form of bears and cats as well.
"tottally ruin the uniqueness" what are you expecting then to be? they will hardly make an unique animal form for every <cat> and <bear> form.