You might want a sand bath, it's not necessary, lots of hamsters enjoy them, though. Shelves are often nice, you can get lots that clip onto the bars of a cage, or you could make your own. You also need a main hideout, like shoebox sized, preferably multi-chambered. How deep is the bedding? Is he a syrian or a dwarf?
There's a thread that holds a lot of inspiration here,
Let's see your cages - New thread - July 2017