grippy wheels are tricky. You can't use urethane, but instead need to use rubber, which is a lot less efficient (heavier and slows you down too much as it takes too much effort to push with the deformation/heat loss). What you can do is buy grippier wheels and swap them onto your board (get maybe a 78 hardness compound) and get wider or bigger wheels too. Easy to swap out. Regarding waterproof batteries, I agree entirely.