Do the roof tiles look a bit wobbly?
You can almost see the shape of the roof battens in places. Makes me wonder if the building is older than it looks ....
Maybe attention was paid to updating the frontage, bays etc but not so much with the roof?
Or is that the (rough) nature of clay roofing tiles? 
I seem to remember that in the original thread there was a suggestion that the house had been extended at some stage, and you're more or less saying that here. Personally, I'm not so sure...
My understanding of the arts and craft movement (which we think this belongs to) is that there was a conscious effort to reproduce typical English vernacular buildings with all their quirks. So, although these reproductions were very well planned and designed, they may have incorporated features to make them appear as though they had grown organically over the years. In this case, the materials and weathering seem pretty consistent across the main house, so I'm inclined to think it was all built at one go.
The building behind the glasshouse is another matter. Is it much larger, or just on higher ground? It also looks quite a bit newer. But what is it? And would answering that help us identify what kind of group of buildings this is, and thus narrow down the precise ID?
All comments welcome, especially as to whether I am right about the arts and craft MO.
Arthur