So far I have identified strong packages in red and blue for color naming, and I think that I likely want to be able to sideboard into one strategy or the other. First, before providing lists I'm going to name what look to me like the payoff cards:
Blue - Force of Negation, Commandeer, Veil of Summer, Scryb Ranger, Mystical Dispute
Red - Torbran, Thane of Red Fell, Chandra, Acloyte of Flame, Chandra's Regulator, Chandra, Fire of Kaladesh
Additionally, Stonecoil Serpent appears to be a payoff for any name. And, if White were going to be included over another color (as mentioned, I'm planning to be RUG right now), Burrenton Forge Tender, Soldier of the Pantheon, Auriok Champion are strong includes for a primary red name (two of them being good for a black name too).
But, on to the deck. I would like to play with a decent amount of mana fixing and deck manipulation. Thus, Oath of Nissa and Once Upon A Time both seem good. If both are included in the deck, I need 45 hits with Oath of Nissa and 35 hits with Once Upon A Time. This means I have a maximum of 10 pure Planeswalker slots. Thus far I have identified Wrenn and Six and Oko, Thief of Crowns as must includes. I'm thinking 4 and 3, leaving me with an additional 3 slots. In a red payoff build, one and maybe two of those are spoken for with Chandra, Acloyte of Flame leaving me with between 1 and 2 slots remaining. I like the idea of both Jace, the Mind Sculptor and Mu Yanling, Sky Dancer. JTMS has obvious power, but I've played some Superfriends style lists before and liked what Mu does, quickly ticking up and protecting your board. Karn could be an alternate route in order to tutor artifacts.
If I play 10 Planeswalkers, and use 21 lands (supplementing some land with the dig cards), that means the entire deck skeleton is:
10 PW
21 Land
14 Creature
15 Other
So with the PW and Land covered, plus the dig spells that leaves me with 14 Creatures and 7 Others. Worth noting, the red payoffs mostly fall into the creature slots while the blue payoffs fall into the others.
Scryb Ranger allows for me to better operate on just two lands, and at pro blue can serve as an excellent blocker for my planeswalkers while Stonecoil is both a great defender and can attack very well if cast later on. I'm looking at something like this for my core: 4 Painter's Servant, 4 Stonecoil Serpent. A blue primary would then use Ice-Fang Coatl and Scryb Ranger to round out the remaining 6 slots, while a red primary would use 2 Chandra, 2 Torban, and 2 Heart of Kiran.
Finally, there are the spells. I'm thinking that a blue payoff is interested in Veil of Summer for sure, and then some mix of the 3 counterspells. A red payoff would instead want 1, maybe 2 regulators, and then some still unidentified spells, possibly Flashfreeze, or Blood Moon, or Force of Rage.
So with all of that said, here's the two possible configurations. I'm interested in a transformational sideboard between them I think, but then some additional SB cards too. And I'm not sure which configuration makes more sense in game 1. I lean towards it being red as Blood Moon can play havoc with peoples mana bases, and they'll play around it in games 2/3.
Red primary name
Decklist
Land 21 (unknown config still)
Creatures 14
Planeswalkers 10
Approximate Total Cost:
Blue primary name
Decklist
Land 21 (unknown config still)
Planeswalkers 10
Approximate Total Cost: