I have taken ballet and modern jazz dance classes and i have gotten use to a slipper over a tennis shoe for the gym since i do calf extensions and floor stretches which cannot be done in tennis shoes

Dont be apprehensive about going down the two sizes and i personally would recommend if you are a full b width to go for a c width the reason being is that you really need to keep the bottom sole in mind and therefore should not wait for the upper to s