Yeah, I re-read that and I was kinda, "D'oh! You put everything in *at once*!" In the past when I've made roasts I use things like potatoes (which I suppose would ruin the low-cardness (I guess it's a word?) of it all...) and cabbage where if you cook them for too long they'll end up overcooked and mushy, so you stagger what you put in.

As far as spices go I'm a bit of a coward unless a recipe specifically tells me to use them; I stick with salt, pepper, garlic, and, if I'm feeling brave, a bay leaf.