I have so many requests to do this week- NFAKJN so, I'll do this one first. Thank you for the question!!
- I'll do this as full Galra Keith so he was most likely raised by his mother, taken away from Earth. He's still half but more Galra characteristics showed in his birth so Krolia thought it was better if she took him and raised him in the blade.
- I always give him a long tail with a bit of fluff at the end, I just think it's cute and it would be great to see Keith with more Galra characteristics, not just his teeth, eyes, skin, or ears changing.
- Have y'all seen Ikimaru's Galra Keith design?
^ Basically this absolute bean <3
- I love the idea of him having lavender/soft-purple skin. Just the idea of it matches so well and contrasts with his otherwise dark color palette.
- Krolia eyes. His eyes are like Krolia's, except maybe a bit darker. But I just love the idea of him being a mini-me of his mother.
- Keith's teeth, specifically his canines, grow slightly when he is mad or feels strong emotions.
- Since I'm doing this as full Galra Keith. His hair is much longer and grows a lot faster too, I would love to say he keeps it that length but no. Whenever it grows, he cuts it off and makes it into his fucking mullet again.
- I love the idea of Galra's being cat-like. Purring, chirping, or mewling if they were pleased or even just sleeping... it gives them such a cute aspect to the otherwise "evil" Galra most people know. So like.. imagine Keith just sleeping and purring in his sleep. That's just the image I wanted to see.
- I'm also gonna add some Krolia + Baby Keith headcanons here: When Krolia first brought her new kit back to the blade, she couldn't leave him alone at all as Keith would cry until she was back at his side once more.
- Baby Keith loved being held by his mom around the headquarters and whenever she tried to put him down, he would cry and cling to her like any other kit would. (Is it obvious I wanna talk more about Galra kits and their whole deal?)
Anyways. I probably could think of so many more headcanons but I legit have no brain space to think this early in the morning so yeah <3