Titan your also correct on the staples, however I think when we talk about staples we are also often putting faction staples in the mix. You are totally right that these are more limited from the getgo but I do feel the full cycle of 1 drops that has Command an Ability and a functional body to combat with can be considerd staples aswell.
The only real exception of the 1 drops seems to be the Dark Eldar Murder of Razorwings.
But when we are talking about 1 drop staples (currently) I think we also mean:
- Ratling Deadeye
- 10th Compagny Scout
- Vior'La Marksman (altough for Tau it's often overwhelmed by Recon Drone)
- Biel-Tan Guardians
- Murder of Razorwings
- Splintered Path Acolyte
- Shoota Mob