When navigating in de Library List, it would be useful have a the list of letters (A,B,C,D...Z) in the right side of the screen. When you have large collection it's annoying scroll down/up the artist. With this list you just select the letter you looking for and go directly to it. This list will be similar to the iSub app for the iphone (see red circle in Figure).
I don't know if this is possible. Anyhow this is a great app! and i love it!