I just wanted to share, and let you know I've made some progress. As soon as I defeat this annoying quirk (icons keep disappearing in some journals. It's very o.O, and I can't figure out what's going on), I'll generalize all the coding so it's easy to customize, make a version with a header image, and post the code.
Unfortunately, you can't guarantee the entries will always be longer than they are wide. I tried defining a minimum height, but it did this weird thing where it shifted everything in the entry box to the middle, instead of aligning it top, and it looked odd. Still, I hope I'm on the right track.