Feature List "Initiative Filter" menu should reflect initiative "roll-up" for group selection

The "Initiative" filter on the Feature List page treats all groups of initiatives as "equal". It would be really nice if it would display based on the initiative roll-up, and then automatically select all the 'child' initiatives when setting the filter. Flattening out the hierarchy the way it does causes the "roll-up" relationship to loose a little value because you can't take advantage of it here. )What good is the roll-up if i can't really "use it" for anything?)