Your progress on the Vault never "expires." Don't sweat it if you open a ton of packspoints past 1,000 will be applied to your next Vault
Its great to get a removal spell back with Belief, of course, but you can also just cast this pretty cheaply from your hand in many cases
Keep in mind, even if you're not playing Game Changers in your Zodiark deck, the fact that your commander forces all of your opponents to sacrifice half of their non-God creatures when it enters will not be the sort of game a lot of more casual players will be looking to play, so make sure your pod is happy with difficult mode
You can cast Control Magic to take control of an opposing Purphoros, God of the Forge if its a creature
You always get a rare or mythic rare that is a card with the showcase fang treatment, a showcase eternal night legend, a borderless dual land, a borderless planeswalker card, or a Dracula series card
We're leaving these somewhat mysterious for those who want to have that experience, but if you want to know what they all do, you can hop on over to the Release Notes