Yes, multi-level cages are a good idea for hamsters because it makes the most of the space. You need non-slip ramps connecting all of the levels too so that your hamster can run around in safety.
It’s still vital that your cage provide at least 2.46 ft. x 1.31 ft. of continuous floor space. Dividing the same amount of space across multiple floors will be detrimental to your hamster’s well-being.