Affinity becomes too powerful an ability when you get to count most of your lands, as do Arcbound Ravager and Disciple of the Vault, and there are also older effects like Goblin Welder that can make the situation even worse
Clive's Hideaway's last ability only cares if you control four or more legendary creatures at the time it resolves
A Glacial Chasm being played on your opponents board shouldnt mean youre now entirely out of the game, and your opponents definitely dont need to untap with their Nykthos, Shrine to Nyx too often either
Living your best customizable life
Unlike games like Pokemon, MTG is a bit more limited in its draw cards and there are several that are considered too powerful and have been banned from multiple formats
I even swapped all of the regular Plains out for Snow-Covered Plains to maximize the effectiveness of Search For Glory, but Im not counting that decision toward the fifteen card limit that I set for swaps