Some sort of integration with Journey Map, FTB Map and Xaero's Map (I think the most commonly used mods at the moment) would be a great addition where the Death Marker left behind would be removed automatically upon the retrieval of the Grave.
I'm not 100% whether it would even be possible, but it would be something worth looking into in my opinion.

I use xaero's world mini and world map mods. There is a setting to remove death waypoints once reached