Avanti West Coast - Glasgow - London

I have used Avanti West Coast to travel South from Glasgow a couple of times and it has been generally smooth and comfortable. The wheelchair spaces (reserved via the Passenger Assistance app) come with a table and two companion seats and are close to an "accessible" toilet. There is just about enough space for me to get onto the train and move between the wheelchair space and the toilet, but I am concerned that it would be more difficult with a larger powerchair/mobility scooter. The toilet is also not large enough to fit a chair and a carer.