3 very helpful features
 

1. to be able to adjust the metronome beat to every 8th note beat -- especially helpful in very low piece, when there are a lot of space between 2 quarter notes beat. And maybe a choice for other - as in 16th note too. 2. to have the option for multiple practice set up (from bookmark to bookmark; and from measure to measure) saved, instead of just one. --- very useful when one is practicing daily on 2 or more pieces at the same time. Actually, it is even very helpful for those practicing daily on several isolated hard spots of a single piece. 3. I know that Notation Composer tries to prevent adding so much features to make the GUI cluttered, just like many other notation softwares I have tried, but you can even simplify the GUI even more by having a "Preference Setup", where one can check on which features only to show up in the GUI.