We had 3 good sized bedrooms, a huge dinning kitchen and a living room. The windows were those beautiful Georgian windows with small glass panels. When it was windy, the curtains would move with the windows closed! but removing them would mean removing most of the charm.
I guess that if you are at home most day, you may manage ok, but, if you work during the day, perhaps it would be too much to come to a cold house at the end of the day, which will take a while to warm up.
When we checked, the best option was oil but because of building regulations we were not allowed to put an oil tank. At the time, it was cheaper to get bottled gas than put electric heating, but nowadays, I'm almost sure the electric heating would be cheaper.
In terms of the work to change it... well, it was not much of a problem they removed the backboiler but used all the existing plumbing and radiators.
I guess that one of the reason why our system was so inefficient was that it was an open fire. The stove may make things much better.
As you are not moving straight away, perhaps you can test it during the spring and summer, and if it is too much, book someone to change it in early autumn.