I have been some ideas about line-bonus in the game! I think it's worth doing so would be if all the notes sung all subsequent notes are like gold or within 2 lines of all the notes are gold! well, I propose to do so for example when collected a certain number of lines is completely sung extra bonus such X2/X3 and so on! I also have an idea that would at the beginning and at the end of the song sounded Ovation is very elevates the spirit! You can invent all sorts of effects example: throwing stars at the beginning!