A lot of games use this technique called dynamic resolution scale to ensure a high framerates, while also keeping the resolution as high as possible.
It usually has a target framerate and will lower the resolution if the FPS fall below it for a certain amount of time . If more FPS than targetet can be calculated it will raise the resolution again.
I think this feature would be highly beneficial for grip as it can suffer from quite some framerate variance depending on what happens.
And since the current implementation of resolution scale can already change the resolution in real-time (if I recall it correctly) it could be utilized to implement it.
I however think it should be configurable by the player. Being able to set a target framerate, minimum resolution and how fast the resolution changes and setting how much of a variation in framerate is OK without changing the resolution would be awesome, as different players will have different priorities.