your hamster is very cute. If you want to get more bedding in a barred cage but with less mess, I used to use cardboard or grass mats tied with hamster safe string to the side. This is a video I did about it if you are interested.
More bedding in a barred Hamster Cage | Cosmic Hamsters - YouTube
Overall the only thing I can think of suggesting is that because it is a barred cage I think you could do something to fill the height up a bit, i.e. a ledge, or shelf in the corners, or maybe a long wooden bendy ladder that you can hang from one side to the other or a tunnel. I have done that before with hamster safe string such as jute or sisal.
Also just to let you know that orange hide thing with the holes in, is made of compressed wood and honey and isn't regarded as being safe for a hamster if it is chewed. Ok for free roaming, but I wouldn't use in a cage. You are not the only one not knowing this, I didn't use to and gave similar itmes to my hamster. They advertise it as 'eddible wood' but you don't really want your hamsters eating wood, far better things for them to be eating. They only eat it because honey has been added.