At the moment it is not possible to nest path formula. However, with very little effort we could restructure the engine to allow at least some nesting. This would make is possible to check for, e.g., home states (A[] E<> p). The amount of changes required for this is relatively small and I consider to implement this between beta 1 and beta 2.
Actually, the approach I thought about will have serious performance issues. Therefore slightly larger changes will be needed, so I bump this to 3.8.