In your area a boiler works out well. If you go with forced air gas,electric etc you will then have air blowing around in the home so it will be different than baseboard.
It is difficult to predict the future when it comes to oil,electric or gas prices. A heat pump will always provide a reasonable utility cost basis but the sacricice is that air movement and more repairs over the lift of the unit.
If it was me I would stick with a boiler system but I would not buy a 90%+ unit since they need more repairs. A good quality 80 to 85 % unit will work well,not need excessive service and last a long time.
You may also consider spending a few $$$ to tighten the house up. Insualtion,windows etc.