Lovely photos. Must've been great to get there on a dry, sunny day as it was miserable and wet the day we visited...!!
Also, just a quick note:
The intention of "One Subject, One Roll" isn't to force anyone to use a whole roll on just one subject - only that the subject should be 6 frames selected from photos taken on a single roll. Therefore, in theory, you could have up to 6 "subjects" on a roll of 36, two subjects on a 120 shot square, etc.....
There's nothing against using a whole roll; in fact, many of us need the wriggle room provided by a roll of 24 or 36 frames to enable us to select 6 photos that we're happy will stand out as representative of the subject.
One of the ideas behind "One Subject, One Roll" was to encourage us to think about the technical stuff as well as the aesthetic stuff - so we get the best out of what we're shooting. I know that, left to my own devices, I used to just "shoot and hope". I'm now finding that I'm starting to get a better hit-rate out of the film I shoot.