I'm all for old enclosures being renovated and used, but they'll be a tad out of place against the African animals! I guess Marwell's not been zoned for some time though so that probably doesn't matter... No doubt it'll be an Asian animal, could be the Anoa moving down again from its current exhibit though! No matter what it'll be interesting to see the future developments.
Your points on the Native Species Zone are sensible NMM, I can't see why Boar, Red Deer, Lynx etc. Couldn't work in the area at the end of the South Road, but that may be too hasty to start speculating on my part!!