When you say you got your thyroid checked do you mean there is an issue there. I have thyroid issues too and I started this lifestyle about 2 months ago. I am hungrier on some days more so than others. I can easily knock back 4000 calories on high carb vegan food if I feel I need to, especially around that time of the month but usually I average out to about 2500 calories. Don't worry about the calories. Eat when you feel you need to. You might gain a little weight in the beginning but it is not permanent. Only eat more raw food if you feel you want to. I keep telling myself in the beginning of the week to eat all raw food but when I get to my "start date" I just don't want to. I think you will continue to stay on the wagon if you eat what you feel like eating that day whether it is raw or cooked.
Depends on what cooked calories you're eating I'd say. If it's low fat/ whole foods then 600 calories is nothing! A lot of veg actually digests much better when cooked.
I eat rice and veggies, or corn pasta with a fat free tomato sauce, or potatoes that have been steamed and oven baked etc.
No added fat or salt :)