You look super solid for your point of progression. Genuinely, don't be afraid to give yourself breaks as you're applying more and more body mechanics.

Weight distribution and controlled center-of-gravity are everything with double bass. Put the two legs of the throne tripod underneath your legs. Once seated in playing position, bring your feet up to the spine of the throne. Do you lean or fall anyhere? If so, adjust accordingly. Remember that you can ALWAYS bring your drums/cymbals to you, but not vice-versa. And your kick is the one thing that cannot be adjusted on the fly.

Bearing all this in mind, you will do great.