Something like "If your deck has 5 or less cards, and you have at least 10 Lightsworn cards in your Graveyard, shuffle 5 cards in your Graveyard to your Deck. This Skill can only be activated once per turn."
Konami already knows that people will spend a bunch of money each month & reserve gems trying to get 3 UR from boxes if others think the cards will be T1. They (konami) will manage