Alternative format idea
What if two people sit down to play Vintage, and rather than bringing an already constructed set of 60+15, they take turns constructing their decks on the spot, one card at a time? This would look like, for example:
Alice: "I pick Mishra's Workshop"
Bob: "I pick Black Lotus"
Alice: "I pick Black Lotus"
Bob: "I pick Ancestral Recall"
Alice: "I pick a second Mishra's Workshop"
After this construction they would engage in a standard best-of-3 match. Would this make for an interesting format?
In the above example, Bob gets to optimize for his opponent by for example not including Mental Misstep.
This can be extended to, say, 4 players, followed by a round-robin set of matches between them, although you'd probably want simultaneous card selections rather than round-robin to save time. Maybe card selections can be made in groups of 4 cards at a time or something.
What would the "meta" be in this format?