Nice. You missed out a few minor events like the one iwth the chest. Oh and its weird but i found the black mushrooms either inside the crypt or the cathedral, cant remember exatly but they were not outside Adria's hut. I just thought that was weird.
The rarest random event I found was the Den of the Fallen. Very similar to the Den of Evil in Diablo 2. I've only seen this once, out of hundreds of play throughs. It is so rare people think it was introduced in a new patch, but it was infact in the game the whole time.
I don't think the Den of the Fallen is that rare. I've probably done it 3-4 times on 15 plays, and I usually don't check all of the areas so I probably missed it a few times.
http://www.youtube.com/watch?v=0XI2ZsQw4dk