It would be so great to be able to read, for instance a bass chart, while recording.
This is one way it could work.
So you have an audio track, typical audio track, but with this new feature implemented into it.
There could be multiple ways to get a score to display - Import a MIDI file, take it from the score editor, import from Dorico project file, detect notation from audio (could be bass notation recorded from piano, a rough bass take, or MIDI exported as audio, etc).
Now, another feature that would be a must, is to be able to overlay the original composition notation with the new notation of whatever was just recorded to see how they line up. You could have a feature to show/highlight both, together or separately, notation mistakes and timing mistakes.
Make it resize able, also have an option to detach it to a separate window capable of an even bigger size (with the audio waveform still in the background).
In addition to this, allow for a separate edited notation (that can be also overlayed with the two other notations), and or, just allow people to write in display notation right on audio tracks, which snaps to grid. Maybe Audio Track Notation versions - when you go to edit either the original import notation, or an automatically generated notation based off recording or imported audio, it creates a new notation version for that track.
Allow notation in tracks to be exported as midi, or a Dorico file, or a midi track within Cubase.