I would like to see some kind of planetary structure decoy, much like the April Fools Day ship disguise. Something we can use to hide special buildings, maybe make them look like a low production level building, or even something new. The strategic benefits could be fun to play with.

Hmm, a low production building? Well, it sounds cool but one could simply add up the building sizes and deduce that it isn't a low production building but is something you want to protect hence I want to steal. I give it a +.5

It could be made to be usable on all structures, which would make it like a gamble.

it could change the planet type and planet icon (along with all the modules)

maybe gas becomes nebula, with all modules becoming gasses like hydrogen and helium
barren becomming asteroid, with the modules becoming....rocks

and so on~

Or I could cover a few useless structures, on a useless planet, hoping you fall for my bait and take a planet I don't want. 5 GP saved, jokes on you. There are quite a number of possibilities.

OOo, I like the idea of something you build on a planet to make it impossible for anyone to see what's there. That would be cool. And yeah, it could be junk or it could be awesome.
It would be nice to have a device that causes a planet to appear as an Unknown planet type though, so you can't see the planet type or size, because a Colossal Demon x17 is not going to have bugger all on it.

you could have a Planetary Signal Blocker and a Ministry of Sameness.

Seems like it would be way easier to allow cloak to affect a planet like a rival ship off the BT. The higher the cloak, the less information you can see, up to and including masking the size and type of a planet

True, hadn't thought of that. That might actually make planet cloaking useful... almost.