Of these, the one I'm most excited for is Titanbreach. Pacific Rim set? Yes please.
The most interesting one is Zhalfir of course: Wakanda mythos writ large? Alright let's see what you got! It doesn't hurt that it's a riff off of Lorwyn/Shadowmoor and Lorwyn Eclipsed, a modern set I loved, with Shadowmoor, a set I'm very fond of.
Plus, I always enjoy it when Magic goes to a place that doesn't get a lot of exposure. It's an opportunity for a window to be opened in my world that wasn't there before.
Which is probably why I feel that Nauctis has something to prove. Atlantis was never a thing. I know, it's a high fantasy staple and truthfully, I'm shocked Magic hasn't done it. But it's such an old trope that I don't feel much excitement about it.
The trailer said that it's the first Magic set-maybe ever?-without flying as a mechanic, which is great, I love that.
It also says that there's a mechanic to replace that aaaaaannnnnd that raises some eyebrows. Because previous attempts at making creatures "unblockable except by X" (shadow, horsemanship) have had some very bad impacts on the game, especially in limited.
Sill, I'm glad to see these sets coming next year and I hope y'all are too.