Every new collision shape requires a lengthy implementation and test. Thus we can't implement an arbitrary number of collision shapes, but only one, if at all.

Therefore I would like to learn about a particular situation in your project where a different collision shape is needed, and the reason why an ellipsoid or a PhysX capsule can not be used in this situation. Dependent on this we'll think about if and which collision shape to implement. At the moment I see no real reason for more collision shapes.