I dont know much Julie, but I know how creative you are about solving problems (eg gabber chewing) so I'm sure you'll get something sorted.
Talking of your Gabber solutions, could you possibly use the larger log bridge to make a wooden ramp for them? I notice you have one in the cage already! (But if you do try it, maybe steer clear of the hamster section wont you? or another introduction may be required!)
the cage looks really good otherwise though, I'm sure Salt and Vinegar like it