Do you really think that the enclosure is too small for the peccaries? I think its quite large if they just made the water section into land. As for the tapir, I think its current enclosure is a better option than this enclosure because its current enclosure has much more shade. The Malayan Tapir needs shade and if it were to be in the pygmy hippo enclosure, then they would need to install a lot more shade because write now its pretty bare.
I meant, the land space was to small for them before, when they still had the pool filled up. If they filled up the pool, it would be a good size for Peccary, but I doubt they would do that. The enclosure is quite shaded by all of the foliage that surrounds the enclosure. If they wanted to add more, though, they could easily add some more artificial shade, such as a tarp or something. The only thing that I think, they would need to do if they moved their Malayan Tapir in there, will be to increase the land space.