The ShiftstonedEternal Power Calculator is a deck-building tool that visualizes your odds of drawing enough Influence and Power based specifically on the cards found in your deck.
I can't decide. The deck without Primal is faster, but this has a few better match-ups using Maul. Neither are excellent tier 1 or 2 decks, but they are really strong budget decks (no legendaries). Playing both around 60% winrate. Crushes temporal control and other slower decks, but is very weak to any lifegain.
What has been your strategy against more aggro decks. They seem to be my toughest match up. Also, I find Sealed Writ lacking, I can get it transmuted just fine but playing feels wonky.
Sealed Writ is definitely better without the Primal Splash. Don't hesitate to play it as power when needed. If it feels clunky, maybe drop to 2 for this list. As for aggro decks, I think the key is knowing which creatures to kill, vs. which creatures to let live. If you're facing a lot of aggro, you might be better-off playing the non-primal version of the deck.