A time saving feature of having a presets list of midi & automation information would be great if accessible directly from the piano roll.
Doing slow & repeatable things such as snare roll patterns, clap patterns, kick patterns etc, would be sped up by being able to build a bank of patterns you can quickly recall, to keep the music flowing and get the ideas down quick.
Could also be a great place to save your un-used melodies or chords from projects where that melody never made the cut, or a place to just save them if you are in a jam session.
They would be easily accessible from any new project you open, rather than having to save them in a project file and find them later, or export them as midi files somewhere, or export them to midi loops and have to browse through the browser slowly while it loads a synth & insert fx, instead of being able to audition different patterns directly in the piano roll of the synth you are currently in.
Synth riser patterns with pitch automation rising or falling would be a time saver also.
In general, it would be a nice place to store midi stuff directly there in the paino roll, just like we do for presets directly on a synth with a drop down menu & list.