Ursula allows you to discard a non-character card of your choice from your opponent's hand every time she quests, which is an incredibly powerful effect that, unlike similar abilities, can be repeated multiple turns
So, a 3 rating across the board, right down the middle
Also, and this is the main bit, you can exile it and the parts of Vecna to create an 8/8 Legendary Black Zombie God token with indestructible
This Vanellope would be a great fit in a deck like that, but I'm not suspecting it to be any good, at least not yet
The problem with many of these spells in Commander are the aforementioned increase in both player count and life totals, which drastically cuts the damage-to-life ratio
Mayaels Aria The only alternate win-condition on the list, Mayael's Aria lets you snowball in value if your biggest creatures go unchallenged