On the no knead:

I've done this a lot, and I've never had a sticking problem. It's possible that your pot isn't well seasoned. You might also go with a more traditional baking stone and steam pan. If you do that, try the silicone parchment paper trick. It's fantastic.

On getting extra sourness:

To some extent, you're at the mercy of your local bacteria and yeast. You get what they give you. There are a few variables you can tweak, like time, temperature, and hydration for the preferment, but ultimately you get what you get.

If you take leftover bread and make French toast (pain perdue), you'll find that sometimes intensifies the bread's flavor. Sourdough becomes more sour. Rye bread becomes more strongly rye flavored.