Providence is much like the Leyline cycle, in that if has immediate benefits if it's in the players opening hand
Copying equipment, auras and counters is sweet, and having a Flying Lifelink creature with an annoying Ward cost goes a long way to making her playable
Making great effect of Enchantress cards, those that cause a player to draw cards whenever they play an enchantment, enchantment decks are often able to create impressive board states while never running low on cards
If we want to be more specific, we need to think about more than just our Commander: specifically, what is our deck trying to do , how does our deck function , and what is the curve we've got
A lot of the time being instant speed also means it is not going to get countered but Decay has them both to be sure