My second attempt at a sourdough - need help!

I pretty much followed the Tartine Olive & Walnut bread recipe with two changes (due to schedule constraints);

1) Bulk fermented for 2 hours at room temperature (4 S&Fs) and then for 22 hours in the fridge.

2) Final proof was an hour at room temperature and then 3 hours in the fridge.

I baked it on a Baking Steel as I don't have a dutch oven.

-> I am happy overall as it is my second attempt. However, I wasn't able to achieve a good 'burst' or 'ear'. I also felt like the bread was rather dense from the middle.

Looking for useful tips please!