1) Per Pattern Mute and Solo Groups.
Mute and Solo'd Pad Selections and State are saved as part of a Pattern. 'last state' is recalled as pattern is activated.
ie: Pattern A1 has pads A, B and C muted and Mute is active on recall. Pads X,Y and Z are Solo selected and inactive. If a user switches to a new pattern, A1 is left in the state it was last in. Save Project would write the state, Load Project would reset the state. Each Pattern stores completely different Mute/Solo group state including selected instruments. Group settings should be able to be cut/copy/paste between Patterns.
2) Standard Tuning Reference for Pitch Settings.
Currently the central reference pitch for each instrument is 'unknown' (at least is 'unstated'). Some sort of reference note would be helpful in the form of Midi Note #, Htz, or Midi Note Name.
2b) An option to output midi to pitch for specific pads. You've got a great hardware sequencing platform in the Spark. It'd be really nice to see you open it up just a little bit. I'd love to be able to make 'tuned' instruments output to their own MIDI channel in MIDI file Exports and Realtime via plugin and Spark's MIDI Out.
3) A proper Midi Reference Spec Sheet. Clearly you're using your own midi communications, and I think that's great, but some documentation beyond 'don't use the private midi ports' would be really great, if only to confirm why strange behavior will result. I've seen some odd behavior while attempting to hook up some other midi equipment, it mostly made sense in the context of 'we made our own mapping, it's different' and in the traditional hardware MIDI world, this should be Documented for users. It would be great to see some optional documentation for advanced users.