I've got caliper brakes front and rear, with a combo lever. I use my coaster brake motor off, clutch locked, to desend steep hills . On the combo lever, put the rear cable furthest from fulcrum, put front brake cable closest to fulcrum, that gives rear brakes a harder pull, with fine tuning, they work awesome .
so am going to strip it down and add lugs for vee brakes front and rear should be fun