Some thoughts…
Navigating in the piano tab would be similar to the pattern editor, for example, short keys for track to track, column to column, octave to octave, and customizable interval jumps, as in jump every 7 notes or other. Or just hit Edit mode and use the keyboard as usual, to program or record notes.
When editing in the piano tab, notes entered gets transported to current track, so if you have Track Scopes open for example, the user can enter notes in one track, click to a different track and enter notes there. The piano tab keeps these notes in one view, for the purpose of time and space relation. 2.7’s sample keyzone handles layers well and can be used for handling overlaps in terms of both note input and instrument. How to handle columns ?
Currently I’m swaying to the idea that when editing in the pattern editor, nothing gets transported to the piano tab. So the user can still do their ninja tracker tricks. For example, disabling Sample Keyzone’s velocity mapping and doing an entire tune out of C-4, not necessarily in that frequency, but organizing all sample zones in that note.
Thank you Ledger for Ticky Roll for the realistic insights, and Thank You Renoise Team, well, for everything.