If you could change one thing to Guitar Hero to make it better/more realistic...
what whould you do?
This is what I would do...
Instead of having 6 buttons I would split them in half to make 12 buttons like this
Which means the screen would look like this
And that way you could have different finger placements so it would make it like you are playing different chords.
Scept each dome wouldnt come down 1 by 1, they would come down maybe 3-4 at a time in different positions.
Bare in mind that these are only Paint edits, if I had photoshop on me they would look alot better but it gives you the idea of what it would look like.