While bringing in wood and having ash could cause some allergies, with a proper chimney and some simple housekeeping, it shouldn't be a problem. Just use common sense and don't bring in a cord of wood into the house, or be careless with the ashes. With 2000 sqft of well insulated area, even a Tundra which is not that expensive would easily heat your home. The radiant heat alone from the furnace would heat your basement. I've seen a few outdoor forced air furnaces around here, and the amount of wood they burn is ridiculous.
+1 what he said ^^^. I heat the same size home as you from the basement with a Yukon wood/oil furnace. ~1200ft first floor to 71-72*, ~800ft second 68* ish, ~1200 basement that stays 68* or so just from radiant heat. Couple points here...
1. A proper chimney with plenty of height goes a
long way to keeping smoke out of the house!
2.Truly seasoned DRY wood. I'd bet those other wood burners homes that you have to stay away from have marginal dry wood.
3.Batch burning...in other words, load 'er up and don't open the door again until the wood is down to coals.
4. Use a good HEPA style furnace filter.
5. My house was originally heated with a coal furnace and has a "furnace room" with a coal storage room off that. If you are concerned with allergies, build a room around the furnace that can be closed off when you are loading or cleaning ashes out. One step further would be to put a vent fan (vented to the outdoors) in there to clear it out before opening the door back up afterwards. The just leave the door open to get heat to the basement. Works well for me.
6. A modern clean burn furnace like the Tundra mentioned above, with dry wood will probably heat your place on 4-5 cords per winter. You can buy those for $1500-$1600 on sale too.
If you are leaning toward a boiler, again... batch burning. You would need to put a large insulated water storage tank in your basement to store the hot water because you load the boiler and run 'er wide open until it burns out. Probably once per day or so. Boilers mainly smoke when they idle, if you have dry wood anyways (see a theme here) Even non gassification boilers can burn pretty clean if they are batch burnt. Start up cost are gonna be a lot higher with any boiler system.
In the end though, your chances of being disappointed with an outdoor forced air furnace are pretty high in my opinion.
I'd shop that insurance company some more...it is usually not hard to find someone that will let you have a wood burner in the house for "secondary" heat for an extra $50 per year or so.
EDIT: After rereading your reply, you are correct, ins co's won't let you have "primary" wood heat, but most will consider wood secondary since you have a propane furnace, then your are good to go. They don't need to know that the propane furnace never runs
. The main thing they are concerned about is that you have an automated heat system that will keep the pipes from freezing etc. if everybody is gone for extended periods