I am sure you'll get more expert answers from others on the site, but a few things that my husband and I have observed. Splenda is a better sweetener than Equal, and you can even heat it up and use it to cook with! I would try to stay away from meat as much as you can. It is full of fats, and you can get delicious protein from other sources, like fish, tofu, beans, etc. And if you like sushi, that is a wonderful source of protein!
Basically, everything in moderation is the key for me. It depends how much of a radical change you want to make in your life. I find that really radical changes don't "stick" as well as more gradual changes over time. Good luck!