Radiant Heat and Tile
Yes you are so right "beenthere", but look at "Texasguy"s query. 1. Take out the old whole house heat pump. 2. Install new bsmt/2nd flr heat pump slightly modified to include whole house A/C.
3. Install boiler supported (or possibly water heater) In Floor radiant heat - quite possibly zoned.
It would seem that "Texasguy"s pockets are recession proof to start with, but to tone it down slightly "WATTS" In Floor Radiant mats could be a cost alternative. Also I forgot to mention last night Texasguy, that you can indeed put tile, stone, marble, wood, etc. down over this mesh. Just make sure whoever does your work knows the radiant is there first. Idid a radiant floor once, had it pressurized and keeping the home warm so the general's tile crew could get started. I came in to check on the heat, boiler, pressure, etc. and found the general had imported an old world GREEK (no Englas-in or out) stone mason who was merrily airnailing chicken wire down to the 1/2 inch durorock that his helpers had just airnailed to the subfloor all over the first floor. I got there just as the system went into low water alarm.