Personally I prefer to open things like that up in a separate tab rather than have a scroll-over pop-up.  Right now, Amazon Prime Video has gone way overboard with features like this, and it's to a point where you really have to watch where your cursor wanders when you've got your hand on the mouse--it's extremely annoying.

I don't think OP's idea is bad at all, but I don't think it's necessary or something that I'd find useful myself.  And I can pretty much guarantee that this will find itself in the graveyard of suggested features that got ignored by Theymos^TM.