I think I'm going to have to rename him Raffy the destroyer
I found the flower basket string chewed through and hanging at an angle, the egg box hammock tipped forwards and a load more cardboard chewed from round the edge of the cage (and a load more substrate all over the floor!). Looks like the cardboard isn't going to work then! To reduce the height of the cage by raising the floor level.
I looked back at the hamstercam video to see what he'd been up to and he's been highly active all night - climbing bars, jumping out of his sputnik. Quite a funny bit where he pulled himself up into the egg box hammock inspected everything then it tipped forwards. He looked a bit surprised then climbed out.
Apart from a quiet patch around 4am he was active until about 7.45 this morning. OH got up at 7.30 and had a chat with him and he was still out.
I couldn't see what happened to the flower basked as the wheel obscures the view of it, but I was slighly concerned he might have got a leg caught and that may be why he chewed through the string. Or maybe he just chewed through it anyway. He seemed fine this morning.
It's like he's spent the whole night trying to escape. Oh well maybe he'll settle down soon. I think he'll be ready for some out of cage time soon.