A lot of great discussion in this thread. The counterintuitive disincentive to improve your colony is what I dislike most about the current difficulty curve in regards to wealth, when the natural (and I think, desired) incentive should be to improve your colony and your colonists' lives.
I think an easy way to encourage that is by changing the "Low Expectations" buff so that it decays over time, rather than with wealth. This would at least remove the counterintuitive/gamey result that your colonists can become less happy directly because of your efforts to improve their surroundings, switching it to a more straightforward scenario where they become less happy over time at a (mostly) flat rate, which you could counter in a more intuitive/natural manner by trying to improve their surroundings.
RE: raid strengths, if the wealth calculation simply weighted unused items and artwork less, that might be all that is needed to make colony improvement feel like a net boon again, when combined with a built in need to increase colonists mood over time (because "Low Expectations" decayed over time).
I think an easy way to encourage that is by changing the "Low Expectations" buff so that it decays over time, rather than with wealth. This would at least remove the counterintuitive/gamey result that your colonists can become less happy directly because of your efforts to improve their surroundings, switching it to a more straightforward scenario where they become less happy over time at a (mostly) flat rate, which you could counter in a more intuitive/natural manner by trying to improve their surroundings.
RE: raid strengths, if the wealth calculation simply weighted unused items and artwork less, that might be all that is needed to make colony improvement feel like a net boon again, when combined with a built in need to increase colonists mood over time (because "Low Expectations" decayed over time).