You look and sound good to me, Hugo, but I agree your breath could be bigger/better.

What helped me find the corners was thinking (oooohhhhh)as I set my lips on the mouthpiece.

If you have good air that you release freely through the aperture into the instrument, you want to experiment with slight changes in your “Shape” that make your sound better (more resonant) on constant air.

If you change the Air and Shape, it will be chaos–you must work on one, then the other, in my opinion.

Then, looking for efficiency–what Shape allows you to change pitch (going up) from one pitch to the next in a harmonic series (open, 1 valve, 2 valves, etc.) with the least amount of movement AND best quality sound on good, but Passively released Air?

That’s what helped me. Hope that helps you. Keep the faith.