At number six is Metallic Mimic, which is a little high for the card on just power level alone, but colorless cards have the ability to see play in many decks and therefore I have it ranked more highly than may have been anticipated
Smuggler's Copter is the most dominant card (by percentage of decks that play it), and while it's featured in both of the big decks, it's also propping up a bunch of second-tier decks like Mardu / RW Vehicles and Bx Zombies, so getting rid of the looter scooter might actually make the format less diverse, as odd as that sounds
Meanwhile, Mycoloth lets us do both at once when enhanced by Willowdusks activation
One way to do this is by using creatures like Rinoa Heartilly that drop additional creature tokens when they enter
Its not only super powerful if you choose someone who is also playing Magic at the time (you get access to their cards!), but its also very funny to just randomly add a player to your game
However, if some of your Lands are meant to be more utility than mana, then you may need a couple more