I think we should absolutely do all of that, for more reasons than just reducing crime. Specifically talking about crime though, I think it becomes diminishing

I think we should absolutely do all of that, for more reasons than just reducing crime. Specifically talking about crime though, I think it becomes diminishing returns. Some countries in Western Europe are not a million miles from that ideal and still have a non-negligible crime rate and homelessness rate. Mental health support is probably the biggest thing missing, at least in part because we (as a planet) are quite bad at treating it. I expect (and hope) that that's the area that will have the biggest advances in medical treatment over the next couple of decades.