This is Milo and Alice, two of the three protagonists in the book I want to write.
Milo is a grumpy little nerd who will eventually learn to take the stick out of his rear and get better about his inferiority superiority complex.
Alice is a perky goth and self-appointed team mom who eventually learns to stop fussing over her boys so much. They won't self-destruct if she lets them out of her sight, promise.
Things I like: Milo's hair, Alice's jewelry and the lace trim on her shirt.
Things I want to improve: making Milo more visually distinctive, Alice's hair.
Mm.. I would look into possible accessories to make milo more visually interesting. As for Alice, I would round out her jaw a little more, its kind of pointy as is. As far as hair goes, I would play around with different lengths and types (curly, thick and goofy, etc), that way you can keep her current style but make it a little more interesting
I like these two a lot, can't wait to see where you take them!
So far, I've rounded Alice's chin a bit like you suggested and added a few lines to the hair she has hanging loose, which is starting to make it look better already.
I've also upped the thickness on the outlines of her eyes, since I'm deliberately going for "heavy eye makeup" rather than just "standard shoujo eyelashes."
Not sure what accessories Milo might have that would show up in a headshot other than his glasses, though...
Currently experimenting with removing little slices from Alice's pigtails so they aren't just a single mass.
maybe a simple necklace chain for Milo?
just to name a few ideas!
if he likes music, maybe he's always got earbuds hanging from his shirt
Hmm, I'll think those over.
For now, here's where I'm leaving off with Alice...
Karu brought up a good point! It helps to think about your characters passions/hobbies/personality/etc and use those to come up with trinkets or accessories to add
Right. I've been thinking about maybe headphones for Milo as part of the Headphones Equal Isolation trope (like Neku from TWEWY).
And since the protags end up in an alternate world with no compatible batteries, said headphones going dead means he can't continue to block stuff out.
With attempts to recharge them anyway using the local equivalent going... badly. Like, explodey badly.
...I think I've just given myself a handy Chekhov's Gun.
/attempts to draw headphones
/...
Welp guess he's getting earbuds instead!

;;;
How do I clothing folds halp
I'm really pleased with how the earbuds turned out!