The frequency of capacitor size depends on the size of the capacitor and the frequency of the size of the capacitor and may be resonant due to any near by inductors irrespective of its size.
If you mean the physical size -- it doesn't.
The working voltage has a major effect because it dictates the thickness and composition of the dielectric. It is also difficult to get a large capacitance in a small volume. So capacitance and working voltage go hand in hand so to speak.
As you increase the frequency the reactance goes down for a given value of capacitance.