New Hampshire fits all your criteria.
1. Relatively affordable especially outside tourist areas
2. 90min of Boston, a big tech hub
3. No extreme heat, decent rainfall, tons of outdoor activities and nature. Ocean, Mountains, Forests
4. Not too far from DC
5. No income tax
As you probably know, South Carolina or North Carolina also fit all those criteria but might be too hot.
As you probably know, South Carolina or North Carolina also fit all those criteria but might be too hot.