So far, I find the split piles mechanic the most interesting. Since our statisticians predict more split piles than we have already seen, what could those be?
So far, we had a terminal money card that has a way to get to the bottom card which is a lot more money, so basically a combination of ecnomoy/payload with a little synergy. Then we have a village where you have to dig through a less desirable pile of cards, but they become pretty good after getting some of the villages aswell. Lastly, we had an attack that needs support, and the support comes with it! I'm pretty sure Catapult will become one of my favourite cards.
So, what other synergistic concepts are possible with this?
I expect that there will be a split pile with a draw card the bottom since there hasn't been any yet. My idea would be a terminal draw card at the bottom with some cheap cantrip on top for $2-3, which you may play from your hand after the terminal draw card (basically giving you the +action back you needed to play the draw card).
Getting a bit crazier: Maybe there is also an alt-vp card under a bunch of action cards? It would be a bit weird with the pile size, although you could play with 6action cards on top and four alt vp cards on the bottom and adding two alt vp cards in multiplayer. (4->6 seems in line with 8->12)
That said, it hasn't been mentioned that the split is 5-5 all the time, right? So it might happen. There could also be some other crazy splits like 4-4-4 or 4-4-2, which I would love to see aswell.