Become the Avalanche Say you manage three creatures where their power matters, Become the Avalanche drew you three and got you at least +3/+3
If you do choose a target, and that target becomes illegal, Waxing Moon is countered, and your creatures wont gain trample
Rakdos Changelings Even though red provides plenty of Dragons to round out the deck, creatures with the changeling ability are nice ways to tie together the commanders that care about two creatures types: Rohgahh, Kher Keep Overlord especially, but potentially also Bladewing, Deathless Tyrant
Be the player with the best mtg game pad at the table
Planeswalkers don't stick around in Commander that often, especially ones that need to survive three or more turns to use their ultimate
You can even use Muldrotha, the Gravetide as a combo piece alongside Displacer Kitten and some 0-cost artifacts