There are no guarantees in life. You could allow hyper-local zoning and still have some terrible neighbors that don't pick up dog shit and have loud parties all night. People trying to "keep property values up" has also led to some terribly discriminatory behavior in the past - we should be glad that such kinds of exclusion are no longer legal.

If "quality of neighborhood" is so important then said neighborhood should, as I stated above, put their money where their mouth is. Maintain a common fund, and commit to match any offer for any house going up for sale in the community. Stop using everyone else's taxpayer dollars to have cities pass and enforce laws to do it.