I agree with Engel, looks great. One lucky hamster.
Apart from what Engel already said the only thing I could suggest is to remove the swinging rainbow ladder/bridge thing if your hamster is able to access that. Hamsters don't really have a strong sense of balance (unlike mice/rats) and I would hate for him to get taffled up in it and hurt himself.
If you did want to add more bedding like Engel suggested you could add grass mats or cardboard to the side of the cage so the bedding doesn't fall out.
This is a video about what I mean:
https://www.youtube.com/watch?v=doZJJHCW1fs