I have friends who keep the sap to make ice cubes for their drinks in the summer.
I think you can use the sap as a sweetener in anything,but the reason to boil it down to 66 brix is that it will keep, but it hasn't crystallized into maple sugar.
I was thinking of using a rocket stove design to finish the syrup off and heat the sugarhouse at the same time. The evaporator isn't designed to heat the place, just boil off lots of sap. The person stoking the arch is the only one really warm. That's why we call it the hot seat.
Sugaring is really fun. It's an obsession.