Ryan Overturf breaks down the concept of Bonus Sheets in draft, going over some versions of Bonus Sheets he's tried in his own Cubes and floats some considerations for different approaches to Bonus Sheets for other Cube designers! 

SCG Bonus Sheet article: https://articles.starcitygames.com/magic-the-gathering/how-bonus-sheets-play-in-my-twobert-magic-cubes/