Thanks, Livhatcher! Sorry to read about your incubator issues. I look forward to seeing your chicks soon.
So on 5...you say mine is darker than your splash. Do you think mine isnt a splash..,maybe a light blue? I was sure it was a splash when it arrived, but as time has passed, I question it. When should the darker splashes usually appear?
Also 7, I am thrown on her too. She is more tufted than yours?
We gave away our splash as a teacher gift at the end of the year. Here he is at last glance:

He was very light with gray tipping. I am very new to SB and have had to lean on this thread to help to be honest with you. I will see if I can get a photo of my black pullet for you when it stops pouring here. She looks more like your last photo. The #7 bird is throwing me bc of its little whiskers but I'd trust @cree57i if she thinks it looks like an SB. NOW, If you are certain that you only had 4 SB eggs, then you are going to have to rule one out.
I definitely agree that the feathered legs are the tell tale of Marans. Of my two pullets, 1 is more heavily feathered than the other, but they are still evident. I'm really not very knowledgeable in areas outside of Polish fowl. I thought it would be fun to hatch some colored layers for my kids. This is an education for me, too!!!