Additionally, weve actually seen both of these mechanics fairly recently in Commander precons
"Dragonite" ( Genetic Apex ) has the Draco Meteor attack, which costs 1 Water, 1 Lightning, and 2 Colorless
Of course, there isn't anything wrong with doing that, but you can draw more cards the other way
Meanwhile, I adore Into the Unknown. Not only is that a killer song from Frozen 2, its an excellent low-end removal tool that Sapphire/Amethyst really does need to keep up the pace, preventing foes from getting too far ahead before you have a chance to ramp up to your bigger plays
In general, Wizards seems to cap the value of reprints in Commander decks in the $10-$15 range, so why does one precon have two surprisingly expensive reprints