After applying throttle, even without throttle you should be able to steer
That should then only turn on one of the motors
I would say so, yes
Generally the higher the better, and not covered by anything metal or conductive, but a rubber? cap would be OK
yes will be fine, mine is pretty low and no reception issues even far out
Big THANKS to you Ludwig and to others who continue to read this thread!! That was a loooong day of youtubing, I now need a beer 
Now I have to wait for the connectors I ordered in China to plug both motors to the PeliCase, connect watercooling coming from the motor pods, and real test everything
First test in a fresh water lagoon this morning!! Semi-conclusive by now, the tow boogie handles fine, control is nice and easy, but it lacks power. I tried with a 55L midlength board and a 570 uha foil so indeed not an easy setup but it clearly wasn’t enough power for two Saite 6384.
https://youtube.com/shorts/8hF5q48dxsM?si=VljHpHfb5G3j5cLE
I’ll dive into the ESCs configuration again… can someone put me in the ball park and tell me what parameter is more effective on power output?
Max Phase current, phase current abs max and battery current are the parameters to increase for more power. But the props also has to match the setup.
Not sure how much phase current the saite can take, on my assist I put it to 120A but I think you can go a bit higher, I wouldn’t go above 130A.
It also depends on how long you torture your motors with high current.
Do you have logging enabled on your bremote? There you can check what is limiting you. I have limited my phase amps to 90 in my dual motor ( flipsky 6384) boogie and can easily get on foil around 40 phase amps per motor (~ 13 km/h). However from your video it looks like my setup has way less water resistance than yours (85 Kg rider, 135 L inflatable board, 1650 cm² front wing). It looks like you are way slower than 13 km/h more like 5-7.
Can you show us more pictures of the design of the board? From the video it looks really interesting? Does it have an inflatable deck?
In general, the way you start is really challenging for the motors, you are sinking the tail of the board right at the time, where the motors are trying to accelerate.
Best way to go is to lay on the board until you are at a full plane and only then try to stand up.
That said, there likely is another problem.
My tow boogie, which is nothing special, pulls me onto the foil from zero speed while nearly ripping my arm off.
But I do not think anyone will be able to help you without additional information. At least current configs or better VESC logs.
I remember being quite conservative when I set the escs so for sure I can pull more meat out of the motors. For example I could only configure max rotation to 38000rpm when Ludwig would recommend something like 50000rpm. Probably because I was too gentle on max amps parameters…
I’m trying to find a way to connect the tow boogie to my desktop computer, I must find an USB extension. I’ll then test different values and send the logs here to cross-check with other people if there’s still space for improvement.