I visited this zoo in August and the tree kangaroo exhibit is basically what is shown in this photo. It is aesthetically ugly as hell, there is zero access to an outdoor area even though the climate around the city of Brownsville is very hot, there are a few dead branches for the roos to climb on, and overall it is one crappy enclosure.
While it may look stark, I personally didn't have any problem with either tree kangaroo exhibit. Size wise they are on par with others that I have seen. To give you an idea of size look at the bottom left of the exhibit and you will see a full sized doorway. As for more climbing structures and a paint job, those are mostly aesthetics. In fact these were some of the most active tree kangaroos I have yet seen (i.e. actually moving). I get the impression that this used to be a koala exhibit. Would you say anything different if it were the equally active koala? As for being all indoors, I kept hearing in my hear those ZooChatters saying "where's their out door exhibit." Of course there I remind you that at least I am typing this from a comfortable, air conditioned, indoor apartment. It is where I prefer to be most of the time. I can't vouch for your own personal situation, but I would venture to guess most of you are indoor as well.
