You need to keep things as simple as possible. The further and more complicated route the sewage has to take, the more chance of a problem in the future, in the current design you've got it running round 3 sides of the property.
I'd be looking to bring the Kitchen drainage down the Left side, and it can run parallel with the surface water across the front to pick up the sewer as it leaves the property.
Bathroom Stub Stack in the middle of the build, take that to the right at 90° and join into the run on the right hand side where it meets. Bend can be used to achieve required angle. En Suite, I'd be looking to connect Basin either into the WC drain, or drop the basin and shower into a Bottle Gully immediately outside the property.
Then decide if you really need 110mm Drainage for the Hot Tub, if you don't, then it cuts out all that pipework going to and behind the rear of the build. Air Con drainage could then go into the Rainwater, it's clean water.