Thank you all! 70% Hydration success

Lurker here for about 2 months.
I took my sweet time and had patience and about 6 failed loaves (well, not failed as in not edible, but you understand my point) I kept trying my starter (created on 29th of November) and a 80% hydration recipe.

Up until yesterday!
Based on whatever was commented and suggested here along the time, I went with 70% hydration.
I have no tools and my kitchen at night stays at 19C / 66F.

Soooo, I macgyver’ed a proofing box, ruining a bit my wife’s perfectly crafted idea of a nicely decorated house.

What changed everthing for me was my starter’s activity. It doubled at room temp during the day at 21C (70F) in less than 4 hours and it started smelling yeasty. Since it’s almost going on being 1 month old, I reckon giving it time is a strong advice.

Recipe based on baker’s math
450 gr Manitoba Oro flour (15%)
315 gr water
8 gr salt
95 grams Starter

Autolyse 1 hour
Incorporate salt and starter
Random stretch and folds (a total of 3 in the span of 5 hours)
Bulk ferment for 12 hours total (obviously including the 5 during which I developed the strength via stretch & fold)
Shape directly, skipped preshape
Stitched it in a glass bowl covered with a towel (will buy a banetton soon)
Cold retard for 3 hours (I promised my wife bread in the morning)
Baked at 230 C / 446 F for 25 minutes in a cast iron pan with a stainless steel tray underneath to which I added water
25 minutes with the tray removed

I will buy a banetton, a dutch oven in the near future.

Result was a very airy loaf, with structure and a very pleasant slightly sour taste.

I will repeat the process every 2 days until I master the outside look since my ear (score) was done manually with a random razor blade.

All in all, thank you all for recommending patience to us noobs.