my advice has little to do with your form, and more about how you look physically(not being gay).
you look real tense/tight, maybe that is just nerves from the camera. I may be crazy here, and honestly my advice probably is not the best but looking at your off arm it seems like you put a lot of energy into keep that arm stiff, so you are probably doing that in other parts of your body. it makes you look almost robotic/rigid in some of the motions. relax some of those muscles until the moment of the "hit". that way you explode through it, and not before it. idk my advice may be totally crazy, but you just seem real stiff. just doesn't look as "natural" as some throws I have seen here
Omega - QMS - MD2 - QJLS - OLF/S - DD - Scorpius
Tell me and I'll forget; Show me and I may remember; Involve me and I'll understand