Yuna is a powerhouse that buffs all of your enchantment creatures with useful perks, dealing overkill damage to the enemy player with trample while regaining life for each damage dealt with lifelink
The fact that this can be cast at instant speed means that you can wait to cast Unexpected Windfall when you have a decent opening to do so
Honestly, the only real problem youd have is figuring out how to get no maximum hand size when limited to black-green
At the very least, they must share blue
Boros has some great Legends that feel a bit long in the tooth to be in the Command Zone in 2024, and Djeru and Hazoret is a Commander that can bring together these powerful creatures with some solid card advantage and get them into play
Bumbleflower and go to town with some commander damage, or, if your board is relatively empty, simply trade it with the scariest army someone else has amassed on the battlefield with Reins of Power and knock them out of the game