I went in to change the way this plugin displays archives (I don't want to show months) and imagine my utter delight when I discovered that the PHP itself was well organized and well written. Two stars just for that. And then! THEN! I found that the actual html for displaying the archives was in a TEMPLATE! a clean, easy Mustache template with no random PHP embedded in it! Amazing! It took me 5 seconds to make it look exactly the way I wanted to.
Now, this doesn't sound like something especially worth crowing about. Right? That's the way code is always supposed to be. But I've been working with WordPress for several weeks now and this is the first plugin/theme/add-on/anything I've found that was well structured, with separation of concerns, and easy to template without tons of repetitive, copy-pasta PHP in the middle of html where it does not belong.
Thanks dude. You made my day.