I think I should have stated my question this way. All things being relative to initial cost of equipment, labor, permits, electrical work, possible construction/structure changes, square footage, etc,, if duct work is 30% of the cost of a heating and cooling system and you no longer need duct work, can't we expect the cost of heating and cooling work to go down by utilizing the ductless technology?

Your existing system has electrical work already done to power it, the new 'ductless' system will need new electrical runs.

A ducted system distributes air to many different rooms using one machine.

Your new 'ductless' machine can't blow air into rooms except the room in which the indoor head sits... so you will need more equipment at more expense to do what your ducted HVAC does already.

While your footprint of 1400 sq ft is somewhat small it is unlikely you will pull this off with only one mini split. So you not only have the equipment cost but also electrical runs to all these additional pieces of equipment. If your electric panel is full already, the costs go up further from there.

Realize mini splits became popular in other parts of the world because the sizes of these properties are very small in comparison to American built residences. They can work in larger properties but they come at an expense in additional equipment and then the more you use the equipment the higher the maintenance costs will be... not to mention repair costs when they break.

They can save on utilities in that if you aren't in the room in which the unit sits you can leave it off. With that said you can do a similar function with zoning a regular ducted system.