There are at least three applications of the UML2 Component which I consider very beneficial to practical UML-based systems engineering:
1st: I make extremely heavy use of the technique of stereotyped <<composition>>, <<inhertance>>, <<specialisation>> "wrapper" Components to graphically and logically organise model elements in BDDs (and in class diagrams) "parasitically", i.e. without stealing ownership of the contained elements. Especially the <<composition>> wrapper Component is very powerful for diagramming and organising hierarchical assemblies of complex systems. In such cases the wrapping Component has Realizations to the wrapped elements, which can be further leveraged to trace the logical groupings. The recipe is consistent with the UML2.1.1 superstructure (although it is not supported in all UML tools). I contend the wrapper Component strategy should be made officially available to those SysML users who wish to use it (at least as a permitted option).
2nd:If one permits the UML2.1.1 Component the SysML <<requirement>> stereotype can be applied to Components so that Requirements can be graphically nested, which is far more graphically stable than just diagramming Class <<requirement>> Dependencies, and can be consistently applied in combination with the existing relationship stereotypes between SysML requirements.
3rd: Components are far better suited to creating orthogonal, parasitic <<views>> of packaged elements than the Package or Model, which both steal ownership.