Encapsulation of notes in a single notation

User story: Let's say one has a really complicated series of 128th notes that is played very often in the song, so often in fact, that it will need to become familiar to anyone reading the score. Let's say one wishes to consolidate this series of notes as a simpler notation. There should be a way to consolidate a series of notes into a single symbol of the user's choosing. Is this possible with the current framework? The articulations and ornamentations palette seem to be a good route to go for this. Just like the user is already able to make custom time signatures, one should be able to "ornament" a note as more complex series of notes. The trill, mordents, and pralls already seem to do this, albeit with no underlying customization.