I could fit both of our cats in that saddle bag. Anyway, are you keeping your hands in one position the entire ride with straight elbows? The aggressive upward tilt on your levers/bars would absolutely give me palm pain if I rode holding those hoods for an hour too, seems like the lever bodies would be pressing hard into the space between your thumb and index fingers rather than distributing pressure evenly across your hands.
Anyway, everyone's fit needs are different and the best advice about hand pain once your saddle issues are resolved is just switch positions a lot, ride in the drops, ride hands free if you can to shake things out every so often, don't wear constricting over-padded gloves, and try to keep your elbows bent a bit to act as shock absorbers over bumps so your hands aren't taking all the force.