The downthrust is normal.

Don't bother trying to take off from the ground. Give it full throttle, point the nose slightly up toward an unpopulated area and toss. Gain as much altitude in a straight line asap. Get your feel for the plane at about 200ft. It flies itself and lands itself. It's also relatively indestructable.

Oh, wind is not it's friend. Fly on dead calm days at first. It's underpowered so try to plan ahead on the throttle and keep the nose below about 20degrees up.

You should get 15-20 minutes on the stock battery. 30 if you go gentle with a slight wind.

The P-51 prop that all HS seem to carry is either the same thing as the Super Cub or works just as well. It's the one with the painted yellow tips.