Details about peep races, furniture and buildings that didn't make the finished game can be found in the game files.
peep races[]
goma, goulifor and haerocan are mentioned in the startopia files
Furniture[]
The ping a tron, a item for the sick bay was modelled and is available in modded games but is non functional and may cause strange game behaviour.
Buildings[]
The Gyro and fighting pit are available as blueprint crates in modded games but cannot be unpacked.