If akki and boggarts are Goblins, these should be Centaurs.

They are pretty much the planescape equivalent of Centaurs. But I'm trying to use planescape specific races here as consistently as possible. I could call them Centaurs as a type and Bariaur as part of the cardname, I suppose, though that would cause there to be a lot of cards with "Bariaur" right in the name, unlike every other planescape race used here.

It's a common practice to use a local name for a race that gets represented by a creature type that is more common among other planes. Think of flamekin & cinder; selkie, merrow & triton.

A trick I like to use to cut down on the constant re-use of the race's local name in cardnames is to refer to it only in the flavor text. I wouldn't be too worried about over-use since the amount of races you are featuring will mean none of them will get all that many cards either.

True, that's a fair point.

Thanks for the feedback, I've been needing some sort of feedback about this set idea. I don't think it's as insane of a proposition as it might seem at first. It is ambitious though. I want to map things over as correctly-feeling as possible.