Structural Support Platform: Size 1, size +3 (one free space on the planet to install, and you gain a net of +2 space) Limit 2 per planet. Cost: 100 energy, 50 ship bots, 20 Durtanium Brackets, 20 Refining Lab Chassis

Orbital Processing Station size 0* resource production +1% population 200 attack 400. Limit 1 per planet. Cost 100 energy, 100 ship bots, 20 Space Elevator Chassis, 10 Phase Cutter Chassis. *size 1 to build, but consistent with the theme of ship bots, space of the planet increases by 1 making it size neutral.

Structural Support Platform: Extra size on a planet, would come in handy, but at a cost of durtainium brackets... i might be swayed to just keep the brackets. That said, i can't fault the idea really, so i'll give a +1.

Orbital Proc Station: +1% resource production for 100 ship bots is way low, even for a repeatable. On a 1k aph planet that's just 10 aph extra. The population and attack are kinda eh as well, compared to certain repeatable legion mission drops. So for me it's a -1 for this idea.

I've amended my suggestion on the second to make it size neutral.

speculation from my side
what would happen if the "Orbital Processing Station" is removed from the planet... would planet have 1 space less again or the bonus planet size is permanent/stackable?
just to avoid abuse later.

Not bad. I think these could work well.
+1.