For some songs, the ability to view track tabs the traditional ASCII way is still a nice to have.
As the track is playing, the current note should be highlighted in a color (green maybe?) like in most modern graphical tab players.
There should also be reload functionality upon source file save; if the new source doesn't compile, keep displaying the previous successfully compiled tab.
1-line info bar at the top
Current track name
Current playback speed
Current transpose amount
Relevant tab metadata if space allows
1-line command input at the bottom
Vim-style / search for bar number or marker name
Track-switching command
Playback speed command
Transposing command
To minimize feature creep, the end user will be expected to maintain additional terminal panes as needed to use the REPL at the same time. All commands added to this TUI should be strictly relevant for session-by-session playback utility.
For some songs, the ability to view track tabs the traditional ASCII way is still a nice to have.
/search for bar number or marker name