Your layouts and accessories are so lovely Hamtastic.
It makes such a difference to the hamster(s) to have some upper levels that are just raised high enough to be comfortable without being too high. I do the same with my hamsters cages and they do love a little shelving and solid ramps/log bridges. These make it easier and safer for them to clamber up and down. I tend to use my drill, small screws and pin nails to add legs or blocks for the legs underneath. My little robo really loves his under shelf dark spaces. he never had these in the six months previous to coming to live with me and he`s loving them.
I like those little corner jervik (?) wooden houses too because they are bottomless and act as a level on their own as they can be cornered inside a cage to save space.