They all, more or less, have the same face.
Also, the Light guy is clearly Narcis Prince from Super Punch-Out!!
...That's more of a problem than is first apparent, actually, since it seems like all they've taken from the element of Light - primarily, from Julious, the definitive Guardian of Light, for whom promo media seems to be teasing a cameo appearance in the new franchise - is "stuck-up rich prig." With Julious, he seems like a stuck-up prig, but he actually cares deeply for those under his charge, and his backstory - and even just little interactions with the other Guardians - shows how his perfectionism is actually an expression of respect and love for his family and those around him. Taking the most surface interpretation of Julious doesn't speak for Luminarise's understanding of character, and depth of character is what made the original cast so enduring.
Additionally: I don't know if Sayo Ichi's art is where it needs to be for this, technique-wise. Koei seems to be putting a lot on this game as the reboot of their former cash cow, but in regards to shading and depth and just plain polish, the character art looks like mid-tier Pixiv. Maybe that's the form teens raised on social media expect 2D art to take?
It's weird, in a way, that the promo stuff says that the heroine is 25, because the apparent average age of the cast has never been younger. Noah in particular seems like he's a third-grader drowning in his big brother's hand-me-downs. What is his big requisite Guardian of Darkness sorrowful backstory? That he can't put his arms down? The heroine's backstory, though, seems very middle-aged, with her burned out at the office and drowning her sorrows in booze. Not sure if the Bridget Jones approach is the best way to reel in a new generation of fans.
I admire the undisguised laziness of them just repurposing of Oscar for their Guardian of Fire. "We're not even trying to make an original character; we're sticking with what works." (Milan is also just Giovanni, though I imagine that decision is a little less commercially-motivated.)
I like Vergil's outfit, though, with the teal and russet with gold & white accents. Though I don't know if teal strictly adheres to the blue oni-red oni scheme he shares with Dante blah blah get that joke out of the way.
It's early, of course (and I'm not the target audience here), but from what's been released so far, I'm not inspired to get to know these characters better. More later, however.