@ZooFan1, based on your hypothetical suggestions, I would prefer a Madagascar mixed-exhibit. It would certainly make that enclosure feel more “alive” with active conspiracies of (at least) two or three species of lemur; and (possibly) some Radiated Tortoises on the exhibit’s floor-level for good measure.
I love the idea of Radiated Tortoises but the ground level for the exhibit is so low that I'm not sure guests would even realize they were there. If large groups of lemurs could be secured they would make wonderful residents but if they only moved in a couple individuals I don't think it would feel worthwhile. Maybe Ramar's former enclosure could be converted for Aye-aye or dwarf lemur
I was an advocate for mandrills at one point, which have similar needs to gorillas and are on the decline overall, but I want to say somebody on the forums proved worthy evidence this would be a bad idea?