"But what are we haulling down from GEO at 43,800 t/year???

I'm sure you'd have some good ideas GB."

I think your guesstimates show the problem with a SE. Even 43,800 t/year isn't enough volume. Space Elevators simply are not the solution to lower launch costs. Probably a viable SE would need to move millions of tons per year. Or maybe a SE will be mostly a means of moving stuff from orbit down to Earth and instead consuming electrical energy it will be a net producer of electrical energy by converting the orbital energy of the space objects. Maybe you will have the situation of 43,800 t/year going up, and 20 million t/year going down. $2/kg for cargo going down, and 500/kg going up with most profit coming from the down freight.