I wanted to add that decreased appetite is an effect of low carb in many people. For most that's how weightloss happens, but I know that mine severely bottomed out the first week of low carb Primal and I could definitely put it away before (I went from binge eater to barely 1000 calories/day in a few days).
I haven't made up my mind about oats yet. It's easier to stay very low carb on no grains at all, but in the future...I do like baked oatmeal, and it's one of the most filling foods I know of.
Rice I've decided against because I had sushi with rice once after going primal and it gave me terrible heartburn.