I'm just judging by appearances, but I'm not seeing Reed Richards.
I did a Google image search on Teller, and from some angles he has a Reed-like facial structure. But the eyes will take some getting used to.
I hope they quickly explain Johnny and Susan's relationship.
Easy -- one of them's adopted. Or maybe one or both of their parents was divorced and brought a kid from their first marriage. I recently read that 1 in 10 marriages in America today are mixed-race; surely a fair number of those are second marriages with kids involved. So a brother and sister being of different ethnicities isn't as anomalous today as it would've been a generation or two ago.