K fucking rules if you're trying to minmax a game or balance your own.
Figuring out things like "what percentage of the time will my starting hand contain the cards I need for my deck to function, and if it doesn't, how many mulligans will it take" will basically ruin competitive MTG for you. I used to buy physical verisons of the decks I made it to top 500 with in Arena, stopped because it wasn't a fun challenge anymore (and lost all interest when they started dragging other IPs in, they'll never get another cent from me)