So I am having the same thoughts myself living in NYC and growing up in DC and have considered the following as reasonable options. I am pretty burned out with NYC so the plan is to move to Park City in a year (when my Fiancee graduates from grad school).
More generally, look into college towns. They are normally walkable, educated, with good culture and things to do.
Burlington, VT (cold, sorry)
Greenville, SC
Charlottsville, VA
Austin, TX
Denver, CO
Boulder, CO
Longmont, CO (home of MMM)
Fort Collins, CO
Park City, UT
Moab, UT
Santa Fe, NM
Bend, OR
Eugene, OR
San Diego, CA
Not all of them check all your boxes but all of them check most of your boxes.