I guess this comes from my oven which is not so good : it heats only from top or botom. When I did it in another oven with pulsed heat (coming from the side), the color was more even.
Great job for a home cook in my opinion. I'd work on my knife skills though, if I was you, get a proper knife not one of those awful oversized meme knives you are using.
Agreed, I've got a real japanese chef knife, but this one looks way better on video ;) and for that kind of cooking, there are no needs of precise cuts. I just remind that these videos are more about entertainment than recipe or cooking techniques.
That's the hole point, i'm not un professional cook. But still it's pleasant to see. (You can read my description to understand my goal through the videos).