For simplicity's sake, I'm representing these in a bullet-point format, but if you're looking for additional effects to round out your lists with some variety, you should consider some of these
The league runs for five weeks, beginning on the release day of the Dragons Maze expansion
When combined with lands and effects that produce more than just one mana at a time, like Cradle of Gaea or even a Voltaic Key to untap the Candelabra, you can easily combo off
With a curve topping out at three, 22 lands should do you just fine
Extra finality counters are redundant and have no effect, but there's no limit on how many a creature can have
This time, I've built a deck featuring 'Ygra, Eater of All,' a rare card I pulled from my very first pack, as the commander