With two lights, run:

both high for lots of light
one flashing one steady or one high one low (alternate to extend battery life)
one on bars one on helmet
leave one home charging your spare battery (battery only charges installed in light)

Agree switch and usb cover are problematic. A smidge of silicone grease on the usb cover helps a lot.
Weight is not out of line (it has a large aluminum heat sink) and it looks fine to me.