One thing I notice (but, this will only help if you are swimming in a pool, not open water) is that you could gain some speed on the way you are coming off the wall after your turn. (I understand that for filming, maybe this was not the objective...).
I have always been coached that the body moves faster through the water when it is streamlined and under the water, rather than breaking the water's surface. So, a person can really work on the strength and stability of the push off (from the wall), as well as staying under water longer, in a very streamlined position (hands together to form an arrow shape, head down in between arms to reduce drag).
I am no expert swimmer by any means. But, I think it really helped my times in the pool when I got to pushing off and kicking in a streamlined way under the water until a natural surfacing point some time well after the competition flags hanging over the pool, several body lengths out from the wall.
Again, only helpful for pool swimming.
"The best rides are the ones where you bite off much more than you can chew, and live through it." ~ Doug Bradbury