So you want to find out how much more uncomfortable you can be with heat coming from ait blowing out of ceiling ducts. The rest of the country uses air from ducts because it is a cheap way to install heating and cooling when the building is new. The experienced and well-to-do have the system the way you have it now, but better.
Don't do it. Improve the present baseboard heating system with baseboard you can hardly see at a very reasonable cost. Then you just need to improve the cooling in the ductwork.