The originator of the concept of Orcs, and introduced it into the world, grounded them in racist stereotypes... Mongols, to be specific... then later lamented that in a letter. Tolkien described Orcs thus
"squat, broad, flat-nosed, sallow-skinned, with wide mouths and slant eyes: in fact degraded and repulsive versions of the (to Europeans) least lovely Mongol-types".
As for the name, the one citation is heavily conjugated, or Orc is part of a longer rood.
Given that the author himself regretted the racism inherent in his creation...
I've seen the human in cosplay effect, too... most strongly in Dragonbane.
I'd rather have the species mods... halflings should be weaker due to less leverage from shorter limbs. Probably should be
Orcs might be stronger biologically. Dwarves made of tougher stuff, especially Gloranthan ones.
I don't much care for race as class, tho' I've used them in TSR D&D and Palladium. And the one shot of Talislanta I ran.
I suspect not correct. I've gotten zero pushback for racial/species mods in core; I've gotten pushback for changing/adding them to games without them. I suspect the actual majority simply don't care.
And I've always (since first encountering species concept, considered D&D "races" as species. then Krynn added subspecies (elves, dwarves)...