Duct size for 1000 ft^2 should be manageable in a central partition on
first floor, with dampers in ductwork to zone heating/ac from single
unit in basement.
"hate" split-units? Certainly no more a problem than system with freon
evaporator in central unit. IMHO, only real negative would be having
yet one more outdoor unit, though that might turn to your advantage. CO
and fire hazard with furnace in attic? Tell that to UL.
Generally, only significant problems with air-movers in attic, that
I've seen, are sometimes difficult access for service, and noise
transmitted through ceiling.
Gonna talk to local contractor soon?