That is a very nice looking cage with a nice glass base

We can't get those in the Uk - there are more options for glass based cages in Switzerland and Germany usually.
It is not a bad cage at all. It is a little small and a bit tall really. But really not bad. The size was seen as perfectly fine for a dwarf hamster about 5 years ago - these days, 100cm cages are the norm. I love the way you have the bedding done with a space underneath for the hamster

Is he already living in the cage? I'm not suggesting you change it but you might want to think about upgrading him later, or you might decide it's fine for him. He has lovely deep bedding and a very nice set up and he'll enjoy that.
It is quite tall for a dwarf hamster, but probably not too tall if you have 20cm of bedding, which it looks like you have

As that effectively reduces the final height.. It's a clever design with the sloping side bars, so he couldn't climb those. There is a possibility that he might climb the bars at the front or back and get to the roof and monkey bar across. So that would be my main concern, as if they do that, they tend to just drop and he could land on a hard ladder.
So I would suggest losing the second shelf on the left and the ladder leading to it, and just keeping the shelf on the right. And then you can stick some hemp mat onto the ladder on the right shelf, so if he did happen to climb and land on it, it would be a softer landing.
He has a nice set up in there - nice wheel and house

He might enjoy some sprays as well
Also just checking - in the cave at the front underneath the bedding - just checking that isn't "fluffy bedding" in there. Or maybe it's kapok? Fluffy bedding (synthetic fluff) is quite dangerous and can cause digestive blockages if they swallow any after pouching. The kapok is natural and there are varying opinions on it - in Germany it's seen as perfectly safe and in the Uk people are more cautious about it
