Just started to bake sourdough. Tips on creating less dense crumb?

Recipe: All flour is King Arthur Flour -120g Starter (fed 40g starter with 20g AP flour, 20g whole wheat, 40g water) -600g bread flour -510g water -12g salt -assorted seeds/grains

  • -autolyse for 1 hour, fed starter and let rise for approx 5 hours
  • -mix salt, starter, and some seeds into flour/water mixture
  • -every 30 min do stretch/fold by stretching and folding top,b ottom, left, right
  • -total of 5 stretch and folds
  • -total bulk fermentation w stretch and fold is 4 hours
  • -preshape - i think the surface did split during this time. it got real loose and sticky after a little bit
  • -let preshaped dough sit for 30 mins
  • -final shaping
  • -overnight proof for about 13 hours
  • -preheat oven at 500F and put dutch oven in it for one hour
  • -bake in dutch oven with lid on at 475 for 25 min
  • -bake w lid off at 450 until golden
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