It could be a production blue. Gray rather than black fluff points to that. I think it will need to feather in more completely to get a good idea of what it is.
Chick 1 has a bit of comb development, but not enough to say it is a cockerel at this stage. Watch the comb for size and color over the next few weeks.
Chick 2 is a pullet, in my opinion. Very small and pale comb.
These chicks have pea combs from the Easter egger side, not rose combs.
Those tail feathers will molt out quickly, and don't mean anything at that age. The comb seems a little large for its age but otherwise this looks to be a pullet to me.
Don't sell yourself short. You do a great job and definitely aren't a novice. The truth is we are all making educated guesses most of the time on here, and all of us are wrong sometimes and right at other times. It's the community consensus that helps people the most, in my opinion.
This one is tough. I'm gonna guess pullet because of the dark wash on the legs, but I'm not certain on this one. The barring is difficult to read, or maybe my eyes are getting bad.
He is not typical in shape for an Australorp. His shape reminds me more of the Langshan type, although he doesn't have feathered legs. He's handsome whatever he might be.