I know it’s possible to have accent notes on top of the system by adding them as part of a drum set or as ossia.
But it would save a ton of time if there was a kind of invisible line for accents above the drum system that reacts independently from the drum kit below. That way it could be written above grooves, bar repeats, slash regions and rests without interacting with the drum kit notation (like creating rests or changing stem directions etc). A bit like the chord track that can be copied separately from the notes below. Or like an ossia that is not showing another instrument but is actually written where it’s meant to be. Would be useful for lead sheet notation too.
I don’t know how difficult this would be to implement and how many users would benefit. I just know that I always need a lot of time for rather simple drum parts when it comes to accents.