I tried all the ones you mentioned, and an OTK #3 (too tight)
Then I took my chances and ordered an OTK #4 And my butt, hips and lower thorso fit very well, the only issue is that the upper part of my body will need lots of extra padding to hold me fit and in place.
I don’t think there are many options for my body shape, other than Ribtech Deep seat, but I don’t want one of those.
Anyhow, that’s what I did and it worked for me. Good luck. Freddy.