[cypher]

If he can climb the bars taking out the top floor might just create a fall risk so take care that can't happen.
Removing the that level isn't going to increase floor space or what you can put there so it won't really make a difference.
I totally understand that you've spent money on the cage & getting another may be difficult although some people do return cages if they turn out to be unsuitable & get a refund.
For now at least I would try to provide a decent house on the substrate in the base if he doesn't already have one as that will be much better for him than sleeping in the house on the top floor.