Looks fine to me. It’s pretty much what I’d expect to see from that angle. Certainly wouldn’t expect to see her belly from an angle where you can see her lower beck. You can’t generally see both the front and back of a person simultaneously in my experience.

Yeah, try actually twisting your torso in front of a mirror. The belly button stays pointing in basically the direction of the hips.

I seen lot of girls do that in the past, I'd say this is accurate

When the right breasts grows out of her left side then this isn't all that legit.
And the lower torso has no rotation in it at all.

The lower torso is rotated slightly compared to the hips. Again, in real life, the lower torso doesn't rotate much when you do this. There isn't just a single joint like you'd have in a robot, each vertebra rotates a bit compared to the one below it (except the rib cage which is locked in place, but the shoulders can actually turn quite a bit relative to the rib cage).

Here's some photo references, the first one clearly shows both the lower abdomen and breasts really look like what you're complaining about: https://bit.ly/2GYJY3H https://shutr.bz/2GXr0KP