Originally Posted by
ganchan
Should I also be thinking about overall weight and wheel/tire dimensions as factors in climbing ability?
No question a lighter bike will be easier to climb with, that's one of the sacrifices you make with a hybrid and/or with a triple crank, they are heavier.
Wheel dimension does play a role but the rider/engine is far more important than whether you are running 700c, 26", 650b or 20".
Tire width is usually correlated to tire weight, so a thinner tire would likely be lighter. Keep in mind the compromise with lighter wheels and thinner tires may well be decreased stopping power on the descent, though.
There are ultra light disc brake rotors available which are so light that they can catastrophically fail on sustained descents, especially if not utilized optimally:
Road Bike Disc Brakes Are Coming, But Will They Work?