1. Ideally, for home baked bread, you always want to use a heavy dutch oven. A heavy dutch oven retains a lot of energy, which provides a consistent environment for the bread to bake in (opening an oven door, no matter how hot, rapidly lowers the temperature), but more importantly retains the steam that the bread emits. This both causes proper crust to form (look for the micro bubbles on the skin of the bread) and makes the entire loaf rise significantly more.
2. The hydration at 70% seems low. While low hydration makes handling dough easier, it also changes the taste - in my opinion, for the worse when it comes to bread. With a bit of practice, proper fermentation, shaping, proofing, and enough gluten formation, even a 78% hydration dough is not that hard to handle. I've baked a 1.8 kilo boulé without any shaping support on a simple pizza stone without having the dough "leak" (in general, if it is "leaking" post proofing, the dough has probably been overproofed and the gluten has weakened).
3. Fermentation time seems really low. Most sourdough types I am familiar with take overnight to ferment, and then 4 or so hours in the proofing basket to be fully ready. I've never baked after such a short fermentation period as described in the article, but I would imagine the resulting bread does not have the full airation, flavor, and texture that it otherwise would.
4. Technique - in my experience and as far as I have read, you do not have to knead at all. Most dough need only 3-4 rounds of "folding" during fermentation, where each edge of the dough is stretched and pulled over itself. That forms plenty of gluten. Shaping post-fermentation is similar, where after the edges are pulled over, the loaf is inverted on the seam and gently dragged around to create surface tension. _Definitely do not knead during shaping_.
For what it's worth, making your own bread is great. My first results were barely edible shame-disks with the texture of hardened gypsum, but after I got a handle on the correct techniques (and more importantly - patience) I have not purchased bread in a store for the better part of a year.