True Viking here boys and girls and Webbie: we really, really didn't do all that much R & P. Just a bad rap for some wild and crazy guys looking for a good time.....in boats.
Back to reality--the OP has fallen in love with an idea. He's got some points, but let me bring you to our Masonry Stove/ Russian Fireplace decision over a decade ago when building here in a winter climate.
Much has been said before about efficiency ( never real world determined ), cost ( a lot more than any stand-alone wood stove ), space ( a home needs to be built AROUND a MH/RF ),
sizing ( byQ can't simply run out and get stones, bricks, and mortar without some PLAN for the structure ), support ( substantial foundation for the weight ), and finally the ART of building one.
Add to those facts, the experience with the many high quality wood stoves we had over the years, the cost comparison ( two high end, at the time, wood stoves new were 1/4 of the NET cost of even a self-built
Masonry Stove/Russian Fireplace, and the extra expense to INCREASE the size of our home to accommodate the MH/RF.
Told before here -- we heat 2000 ft² with NO central furnace backup, 24/7, 2 wood stoves, harvest 6-8 cords from our woodlot each year, flush/running water/showers, and we don't enjoy discomfort.
Some advice byQ: do due diligence. "Do due diligence" ( rhymes, huh ? ). Get out and see actual MH/RF units in use in winter. We did. They do the job well and effectively with caveats. So do all the wood stoves we use.
And please: get off this "Euro is better" schtick. They have some serious problems ; one of which is a lack of easily gotten firewood. We'll save the higher end political and economic talking points for later.