Some players prefer to avoid any such pain of handcrafting, and instead use a legend - a table that maps some of the physical cards in that player's deck to other cards that they would like to have instead
The current system is more arbitrary, and a lot of Rule 0 talks end up in the controversial "My deck is a 7" statement, which doesn't help determine what decks can do, what their win cons are, and how power-crept a given deck truly is
Well, you might know, actually, because the discover keyword action allows you to dig into your library and cast something for free
On top of that, you included an Atraxa as an extra card and I actually already run an Atraxa deck
If left alone, they'll quickly grow from menacing to overwhelming proportions, much like how super mutants continue to grow as they age