I thought I should start this, because I have predictions based on cast-members' photos and such.
In no particular order, I'm guessing Sophia Nomvete and Megan Richards as dwarves. Based on this photo, they both have broad frames. It's just an observation, not a criticism. Your average dwarf has a broad frame in pretty much every picture I've seen. However, here's a pondering. To female dwarves in LOTR have beards? They did in Jackson's Hobbit, and the Dwarrow Scholar agrees with that depiction. Scroll down to the voice section. So I suspect that we'll be getting women with beards.
Maxim Baldry is at least a part-time musician, which suggests elf.
There's something about the faces of Joseph Mawle and Ismael Cruz Cordova that say Sauron to me. Mawle if he's ugly, Cordova if he's pretty. Not that Mawle is acutually ugly, just that he can be made up that way.
Look at this picture of Tom Budge! Does that say a relative of Thranduil to anyone else? Something haughty at any rate.
Charlie Vickers played Sean Bean's son in the TV series Medici. Which means I want him to be a distant ancestor of Boromir. I'm probably entirely wrong about that.
Dyan Smith has a face that says crusty old Numenorean king to me. Recently spotted with a decent beard. Numenorean or dwarf. Elves rarely go for beards.
We'll see how wrong I am.