I think the problem you may have here is your attempting to emulate your sport with what you do to get generally stronger. SS is a barbell program that uses exercises with the most mass, longest effective ROM, and places an emphasis on load. Dips like you said have problems with the apparatus and risk of injury. Your maybe in a age demo that make wtd dips scew riskier than favorable. Standardization is also a problem since you have to take into account both the apparatus and your BW. I believe most think of dips as a great augmentative assistance exercise for your presses. That however does not make them a main lift. As far as the status of the bench im sure you can find a solution if the cleanliness is the real problem.