Temporary or late bronze age equivalent type architecture seems like the right approach. Akin to the traditional architecture of N.American natives.
https://s-media-cache-ak0.pinimg.com/236x/3b/49/83/3b49837a1a3b207d0658fcc041bf3fce.jpg
I would probably have created a model of a longhouse, like the two seen at the bottom of the image. I would also suggest that you incorporate high-tech Tau greebles, to show that while the Kroot prefer their traditional huts, they're also using Tau gadgetry, for heating, communication, cooking, etc. It would make for an interesting contrast, while also make your buildings seem more realistic.