These colors tie to treasure creation, payoffs for spending mana from treasures, and artifact sacrifice
While she cant gain control of an artifact creature she can come in with ninjutsu
For a while, Ramp;D used a term "marquee card" which meant it was a splashy card that drew a lot of attention to itself and did something that had never been done before
Smothering Tithe in particular plays very nicely with this card, letting you draw a card on each players turn in a Commander game
If you draw an awkward hand with too many combat tricks, you'll be forced to use them in imperfect situations, playing into your opponent's hands
Goad forces that creature to attack if able, but Alela wont allow that creature to attack you, thus forcing combat between your opponents and sowing chaos on the battlefield