wow... Im looking at a large btu boiler and h/w tank that could service the town
Judging by the fact you have 47 A/C compressors surrounding that mansion I'm going to advise you should indeed tap into your existing h/w heating system for central heat (you need more than a living room stove). your not going to want to deal with a stove anyways... your clearly to busy to worry about such things and frankly a person like you in all likelihood will have better savings by utilizing your time doing whatever it is you do and simply installing a pro coal boiler as an add-on! as Dave explained this would likely pay for itself in a flash! (2 seasons i would guess). You will also be much warmer through the winters and would not yell at the kids so loud when they leave the door open
Your plumbing is fantastic, you have like 3 or 4 zones already, your house is newer (so I'm sure its fairly well insulated already)... You obviously have ability to have a professional install done if you wanted to bite the bullet and go for it (the sooner you do... the earlier to pay off comes! you will make gains very fast that even the stock market could not do you for you!)
EFM, AHS, LL AA220, KeyStoker seem to all receive the most consistent/reliable feedback and reviews over many years from what I see... I would start researching those and maybe some boiler pro's will give some insight on how best and least expensive to add on in your case.