Archaeology achievements? 100% complete! And apparently, I now belong in a museum, or something.
With two rares to go, I shifted my emphasis from Kalimdor to Northrend. I figured that since I had found zero Vrykul or Nerubian rares, I'd probably have a better chance of getting one of those projects relatively quickly if I worked in areas I'd not done much in before.
Looks like that was a good guess. Night before last, I solved the Vrykul Drinking Horn for rare #19, and a push last night netted Aeth the Blessing of the Old God for rare #20.
Also, providing evidence that the RNG has a sense of humor, after getting the Blessing for rare #20, I cleared out some Night Elf fragments that I had remaining... and now have Tyrande's Favorite Doll queued up for the next time I want to do some digging.
Once that happens, Aeth may finally get to replace the tree stump she's been dragging around for the past couple of months. The wonderful thing? When she finally gets a better trinket, I can pass this along to Laenshield or even Aeven. Yay for account bound epics!