It would be great if there was an option to add 2D rings so I could save processing power and have better distant rendering.
While I can see that it can make sense on low end systems, we strive very hard to make everything properly interactable, which means that the ring should simulate as a collection of particles and be able to warp when attracted from above or below the plane of the ring.
The same goes for the tail of a comet which could easily be handled as a graphics object, but that would be rather limiting if you want to interact with it.