The LE diet is kind of what you make of it. You can go hard-core or make it a softer sway. I would personally try to skip fish when you can b/c it's a healthy meat but if you need it once in a while, you could probably do it. Just figure it into your LE daily values of course!
Beans are okay as long as you can fit them into your daily LE values but watch out for the sodium in baked beans b/c I think it's pretty high. Also, beans have quite a lot of protein so you'd want to eat just a little bit.
ETA...Here's Atomic's take on fish (or any meat in particular):
If you do eat any fish, make sure it's not salmon or any of the kind rich in Omega 3s...