My understanding is that a conductor has a certain power carrying capacity. Power is volts X amps. Losses are proportional to current carried; raising the voltage drops the current at a given power level which is why the power company transmits their power at high voltages so they can use smaller (= cheaper) cable for a given power level. By doubling the voltage I halve the amps transmitted. This, as you note, allows me to decrease my VD. If I take a 5% VD as acceptable, I can draw more amps with the same VD at higher transmitted voltages, can't I?
My electric coop gave me one option: pay them $18,000 to extend their service 2000 feet to my house. Their transformer outputs 480V at my property line. They would not give me 480V and allow me to bury my own line and extend the service to my house and step it down to 240V myself. They told me they would give me standard 240V service at my property line and that if I wanted to extend that 240V service 2000 feet to my house, I was welcome to do so. I don't have any other experience with utilities so I do not know if this is hard to believe or not, I only know that they have 480V available at my property line but they would not give me access to that- they would only provide me with 240V unless I paid them to extend their line to my house.
As I said, I have been using this 2000 foot line for a year with a 3/4 hp well pump, table saws, band saws, lights, etc., and have not had any problems to date. I would like to do this so I can add additional loads in the future with out a larger VD...
I am assuming that my loads will be well balanced and therefore have not made a distinction for 120V loads.