I'm actually really enjoying this seasonal mode, and have played it a lot this month. I enjoy the challenge of both essentially having the same hands, and the ways you can affect what your opponent is able to play by playing those cards first. Also, because passing isn't really a thing, there's less depth to the strategy, which this month frankly I have enjoyed - it's nice to have a game that's more casual and less taxing, in these stressful times.
I also really enjoy the process of being confronted with your opponent's entire hand in turn 2, and figuring out what kind of a deck they are, what their strategy is, and how to counter it, and how it could counter your strategy - or indeed whether to play their strategy better than they can. Maybe it's because I've always really enjoyed Assimilate as an archetype that I get on so well with it. I completely agree with
@DRK3 above about the main tactics to keep in mind in your deck building, that carryover means a lot (as round 2 & 3 will be 3 cards each only), that cards that can pull other cards out of your deck (and not your opponents') are great, and that big opening plays are important.
That said, maybe I'm enjoying this mode partly because I appear to be good at it - my win rate is probably around 80%, mostly 2-0 (though they're easy to achieve if you manage to win R1 with your leader intact).
I've played lots of variations on an assimilate deck with double cross, that's mostly been a Shupe singleton thing too. And then whatever nonsense to finish contracts, like beasts and vitality. Having a deck that's mostly trash is not necessarily a disadvantage in this mode
