In Chess, Rooks are more valuable and powerful than Bishops and Knights. Why are they little nubbins in this game? Those guys ought to be Pawns, especially since their attacks are rather one-note. And if we're going by size between Knights, Bishops, and (dilapidated) Kings, then actual Rooks ought to be house-sized.
Also, the angular worker drones ought to just be Serfs considering they're purely noncombat. Plus it fits in with the feudal theme.
