That motor is definielty capable of 1500w, pretty much continuous. It could still melt on a long enough hill, but I'm talking climbing a mountain, not a "hill".
You are wanting more like 3000w. It still works, but you do have to watch the ride duration. Melting one is possible at that wattage. Most of us do a few mods, like bigger phase wires so we at least don't have to worry about melting the wire in the axle. You can just replace the wire with fat stuff to axle, then the small wire left in the hub can heatsink to the fat wire.
You should have no big problems with 3000 w rides of 8 miles or so, about what you get from 72v 10 ah.
You will need a superb torque arm/ torque plate, for a motor that puts out 2-3 hp.