I would candle the eggs at least once a week, also i would smell every egg on that occasion. The developing embryos can still die and an exploded stinker-egg in your incubator can ruin the whole batch.For sure you have a point, the eggs are already quite "crowded" but I can see the veins very well and they are going vertically as they should (not floating in a horizontal circle). The air sacs are quite small to my newbie eye. I think they are doing well.
Can't take a photo because I'm using the mobile's light. And a sawn-off medicine bottle. Painted over with beehive paint.
If they are OK now, it's not very likely they would suddenly die before I open the incubator anyway at hatchday-minus-two, correct? I don't have to look again? I would prefer to just let them be since progress seems good.