Hey Jeff, some great images there - you're nearly selling me on the 40mm f/1.4, just when I was about to get the Summaron 35mm f/3.5 instead!
If you're after a bit wider, the Voigtlander 28mm f/2 Ultron has really impressed me in the ~8 months since I got my R-D1, my only concern with it is that it seems to be reasonably contrasty, which (with the contrasty sensor) can be a plus or a minus. I'm considering the Summaron mostly because it might be a less contrasty option to have on hand, which would open up the shadows just a little in the crisp New Zealand sun for me.
Anyway - the 28mm seems great wide open, so for low light / shallow DOF at (relatively) wide angles it's ideal. To get a wider & faster option costs a great deal more, the next option seems to be the 25 f/4 for most people, which is quite a bit slower for a tiny bit wider...
Look forward to seeing more of your work,
R!