Peridot not really. She seems to be a mechanic someone Gem society would need nowadays with all the new technology. Besides, before they started arguing, her talk with Yellow Diamond seemed balanced; Pearls don't seem to be allowed to talk back to Gems above their rank but Peri can.

Anyways, you're still right. The Diamonds aren't building a society, they're building the perfect war machine and they're going to use it on all of the universe. One single malfunction (malfunction=Gem disobeying) could lead to downfall so they have to be very controlling. I don't think they see the others as beings more like spendable tools that can be easily replaced.