This is only minor, but I thought I'd say it anyway. You left out one ruin enemy. Slithering Ruin. They're really quite common, but if people just ignore them it's gonna take longer to get the achievement for 100 ruin enemies.
Edit: Also, for Calm in the Face of Death, I did it at the bit with the bolterflies after you pick up the pepper grinder. Just let them sap your health until you're down to one rose then kill five of them. And if you kill five in succession you should get 2 achievements at the same time
I found it easier to do it at that bit because if I tried with other enemies I always seemed to pick up another rose when I didn't want to..