Shortcut for adding cards to a set

Not sure if this has been brought up before, but it would be nice if there was shortcut to add cards not entered in a set when you're on the set page.  For example, when you click on a specific set and it lists all the cards already entered....many times there are missing cards.  If there was somewhere on that page where you could quickly enter more cards or a link that would take you to the add more cards but the set would already be entered.  

One more possible idea....when looking at the cards in a specific set, if a card we're looking for is not listed it would be helpful if there was a spot on the page where you could just enter a name, card number, print run, etc. and it would just add it to that set.  This may eliminate cards being entered into the wrong sets as well.