This faction might be an interesting candidate for something like the FfH "Fallow" trait. The general idea is that they don't use food and grow by... other means. In this case, I'm not sure if harvesting slaves, or building more robots would be more appropriate.
Maybe they could have an upgradable palace which requires a "genius" slave to upgrade.
This faction could also vary a lot depending on the leader. You could the crazed Calculator, "The Warrior", or Simon Barnaky, all with different play styles.