What kind of heater should I change to in Indiana?

I have started looking into different heating equipment than what I have.

Currently my husband and I rely on a central heater and air conditioner for our Indiana home.

We live in Evansville IN, AC isn’t really needed. Sure there are a few hot days in the summer, but nothing we can’t handle. The two of us prefer to open the windows and let a fresh breeze in amway. It clears out the air and removes odors. So having a cooling system is a waste of money. I have been looking at strictly heating only systems to save money. I am just not sure what I want. It seems like a boiler system is the most powerful and efficient of them all. The con of this type of heater is that a boiler is super expensive. It is also quite large and needs to be fitted in the basement. It can have piping hooked up to it to serve as the water heater, radiant heater, baseboard heater or a snow melt heating system. It is very versatile. I just don’t know if I have that kind of money. Yes overtime I am sure it would pay back for itself, but it is such a hefty expense. I have looked into furnaces but they require ductwork installation. My house is older and I am not sure it could withstand this difficult process. That leaves me with a fireplace or electric heated flooring. One isn’t that powerful to do the whole house and the other one requires my current flooring being ripped up. I don’t really like any of my options here.
air conditioning installation Evansville IN