Just use 'colonization'. That's been my take since I first heard of this 'debate' especially on dead rocks like Mars or so. It's a non-issue, and blowing the wind out of the sails of agencies and missions over 'loaded language' and 'mindsets' is barely worth the effort. Humans are not dull robots, we're not going to march offworld under the auspice of science and goodwill only, profit and greed and being the 'first' and for the challenge is what drives it, and when we staple that down, we get sluggish 'progress' - look at the Moon Treaty, the Outer Space Treaty. No matter how you feel about them, you can't deny that they had a diluting effect especially in the semi-private and private sectors.
And when there ARE other beings on a world or claim it, then having the colonists being greedy brutish assholes can work, or a misunderstanding, or a slew of stories that confronts the problem, when it actually is a problem. TOS had this with the Gorn and Cestus III. They called that an 'Outpost' by the way, not even 'Colony', but the Federation had, unknowingly, entered the claimed space of another power and a conflict almost started over it. Humans seem to still have an 'itch' in Trek, it's why a slew of them are in Starfleet in the first place, and those get filtered out by the Academy and organization to be straight laced professionals, there's a whole other angle that could be approached by private citizens biouvacing across half the local bubble, with a 'claims and other aliens be damned' attitude at worst.
