in the default PlanetImprovements.xml, there ar ea few typo's keeping some of the improvements from being available.
Galactic Monument has [S_TechRequirement]StarFederation[S_TechRequirement]. while the TechTree.xml has the ID as simply StarFed.
Nanorecorders has [S_TechRequirement]Sensors2[S_TechRequirement] as the requirement, but techtree.xml has it listed as Sensor2 without the extra S.
these two below are probably intentional.
Historic preserve has [S_TechRequirement]ArtificialSatellites[S_TechRequirement], that doesn't specifically compare to anything, but there are some starbase modules with similar names.
Anti-matter power plant says it needs Anti-Matter Power Plant, but that doesn't seem to exist at all