This is about the conclusion I came to - makes sense to put a popular species in an area more guests will be able to see it rather than at the back of the zoo which may be easily skipped.I think it's a more central and visited part of the zoo, so it makes sense to put a "star" species there. It wouldn't have suited much else par another species of small cat, and I'm not sure there's much availability at the moment, par the lynx but the enclosure doesn't seem appropriate IMO. Curious to see what future progress holds, especially considering the peculiar design of the current red panda exhibit.
Though for what it's worth the enclosure was initially designed for coatis - which were moved from the Coati Roundabout after years of breeding there and doing very well. The reason Marwell went out of coati was no fault of theirs - it was that they were listed on the European Invasive Species list subject to strict regulation and prohibition of breeding [and remain there as part of 'retained EU law'; which could be overturned but as of yet no one seems particularly moved to do so] and so Marwell had the coatis there for 2 more years before eventually sending them off.
My main question with adapting the [ex-] clouded leopard enclosure for red panda is that the viewing suits something that's on the ground for a decent amount of time and decently large in size. What would be inconvenient is if the panda climbs up and you can only see the tip of its tail from the ground. Unless the 'stairway' to the side of this enclosure is again in use?
Saying all that... given that they have now gotten rid of the old tamarin area and have planned for it to become a nature-garden-area-thing one must wonder if they intend to extend the reach of the UK Native Species Zone [still not partial to that name] to the rest of the Fur, Feathers, and Scales area. Which was redeveloped in 2006 from what was a paddock for Ankole Cattle and a children's farm.