I'd guess that this "look" has been market tested and found to appeal to the key boys demographic. I'm reminded of all those superhero toys that are the same character (like Batman and Spider-Man) over and over just in different sorts of armour/costumes.

Besides the new "Beasts" (which may be show accurate) all the other toys revealed so far are the existing cast (and often existing toys) with new "costumes". Less range of "characters", more repeats. At least the Cyberverse line has new figures coming, although again not many new characters.