A fireplace (the old open masonry kind) is massively overrated. I have two in my new place. They just suck semi-warm air out of the house and blow 95% of the heat up the flue. I never burn them except on a damp day in summer, even though I have endless wood right here on site.

I just converted one to natural gas, with a pilot light and designed to run full time without requiring the electric fan. This will give us an upstairs "nest" that always works, since our NG grid is largely independent of the electric grid. The price was a bit of a shocker, but it will be used regularly for three seasons and (at 85% efficiency) will save more money than it cost over the long term.

For the other masonry fireplace (basement) I have a simple hunter stove that just fits inside. I also have single wall chimney pipe and insulation (for a chimney seal) so I can jury-rig emergency heat to keep the pipes from freezing. Obviously this would have to be supervised at all times, both to keep it fed and safe, as insurance would laugh at me if this caused a fire. A battery powered CO detector would be essential also, because dead lasts a long time.