Hi Colin
I like your idea for architectural... as you say, something different and it's nice to see something other than a building. The only thing about the theme for me is architectural shouts "detail" or "macro" (in the non-photo sense), i.e. either small and intricate work or whole building/construction. Obviously there might be exceptions, but the link to the theme could have been even stronger with a wider viewpoint and be able to see the architectural "plan" of the walls? I'm not sure quite sure what I'm saying any more!
The sign is a tricky one: in some ways it distracts, but I think your instinct was right to have something else in the scene. I do like the arch right of frame on #2, so perhaps that could have been an architectural detail to make more prominent?
Exposure looks a tad low to me in both (just going by eye)? I think your DOF choice is very good - you've blurred the fence sufficiently without losing the sky and kept the walls sufficiently in focus. That's a really tricky one to get right and I think you've nailed that.
I find the hill appearing over the wall in #1 to be slightly distracting so the POV in #2 definitely works better. Finally, I'm not sure the ground helps things - it's quite artificial but it is what it is!
I do like the contrast boost in the sky and your processing there. The lighting overall is lovely. Two solid shots which are on theme enough for me... onwards and upwards to the next one!