I recently hacked the location of a really good but unoccupied planet. However, the guy I hacked the location from is in a legion with players much higher level than any players in my legion. He's also much more battle equipped than I am. Should I even bother colonizing the planet?

You can colonize it and hope he's not big on invading or use a Planet Flux(40 GP) on it afterward.

what is "really good" to you might not be "really good" to the members of top legion. Many of them ignore things below Very Large Ultra Rich etc.
Artifact planet of the same "size" are usually worth more thou.
If you are low ranked, colonization won't cost u much so might as well do it anyway. Even if u lose it later u have enjoyed its benefit for a while. Just DONT put mission structure on them(mission structure means zolain analysisor, quantom-hydros etc that you will NEVER get more of)
If you are high ranked... You should be able to finish Aeon moon and get to the free ghetto flux, use that

You can brick it for a week and use the mission flux.

Alright I've colonized the planet. Thanks for the advice. For the record, I'm level 35 and it's Very Massive / Resource Rich.

If I lose it, can I occupy another planet without needing the next tier level? Also, is it worth building soldier outpost(s) on the planet?

what rank is the other player?
a very massive rich gas would barely fit in my planetary standards.

I don't remember but somewhere between level 40-60.

you should have no trouble at all keeping it if they didn't even colonize it in the first place.

Okay thanks a bunch!

40-60 lol, i thought u were talking about 500+
yeah, planet invasion around ur lvl is on the hard side, just put up 4 def, 2 atk and 2 population module and u would be set
VM i'm guessing is gas, so those can't have populations modules, so u might have to waste elevators if you think it's worth keeping.

LOL I was 2 seconds away from checking all my VM/Rich enemy occupieds...I guess it wasn't mine