I knew one way to get some e-mail going was to post a puzzle where I might not have found the complete set of possible answers. I really did try to find every word in the diamond, but I had a sneaking suspicion that a few had gotten by me. And yes indeed, that turns out to be the case. Maria Gullickson was the first to find TROD and ATOM, and Adam Wood found the word ARID. Thanks, guys!
(The good news is, people are reading this blog! Yay!)