I wanted to not present something that was far superior and enslaved the standard human but perhaps had tried and failed sometime past. Thus creating a group that while no longer in power may have some natural conflict with other groups.
Within the game back story I have never wanted the Beltinovite to be children of the architect as it were, but rather some sort of natural evolution of humans. I wanted them to have their own creation myths that often make claims that directly contradict other creation stories. I am not saying they are in fact correct but the Beltinovites believe them as true.
From a physical perspective the beltinovites are generally short and slender; perhaps around five feet tall with light builds. They have dexterous hands and large heads. Along with this, they bear some elements of their trans human heritage. They are generally not prone to disease and are long lived by human standards. Some family lines bear more isolated modifications. adaptation to non standard environmental condition is present in some lineages.
If put into Pathfinder terms they would look something like this.
+4 Intelligence, –2 strength: The beltinovites are intelligent but poorly adapted to physical labor.
Small: Beltinovites are Small creatures and gain a +1 size bonus to their AC, a +1 size bonus on attack rolls, a –1 penalty to their Combat Maneuver Bonus (CMB) and Combat Maneuver Defense (CMD), and a +4 size bonus on Stealth checks.
Cultural skills: The Beltinovites have +2 to all knowledge skills.
Cultural feats: Beltinovites can take special feats related to their particular morphology.