Would anyone care to guess genetics with me on my backyard flock?

[NatJ]

Thank you so much for the kind words and the genetic information as well. I do always love to learn about feathers color genetics. I’ve played with Chicken Calculator a lot as well. I find myself looking at “no image available” constantly when trying to recreate my flock lol.

Definitely frustrating to run into "no image" on the calculator! I've found it helpful when I'm trying to understand some things, but it definitely has its limits.

I also have my suspicions about the pattern gene just going off the second roo out of the first clutch. When I look at his saddle feathers they don’t have the straight across barring. Instead it looks like messy penciling.

For that particular cockerel, I think it's just barring, not pattern gene. The barring gene does not always make lines straight across. Sometimes they are little v-shapes, sometimes they are just kind of messy. "Cuckoo" varieties of chicken also have the barring gene, but it doesn't make really nice lines (hatchery-quality "barred" birds can have that too.) The really straight horizontal barring seems to be something that requires other genes and careful selection to get right (example, show-quality Barred Rocks).

And also the only roo in the second clutch looks so much like Mille fluer… that’s why I have my suspicions.

Mille Fleur is typically a Gold Columbian coloring, plus mottling, but no pattern gene. I agree that male does look rather like Mille Fleur coloring. I'm not sure if he actually has the Columbian gene or not, but he definitely has areas of gold and some black plus the mottling.

Whatever is going on with him, I think at least one of the pullets in the second clutch has the same thing but with silver. (#4 of the 6 photos from the second clutch.)

The E locus is just a master class in confusing me when it comes to judging just by looking. I feel like I have a better understanding than before tho after reading your comment.

Yes, the E locus trips me up too!

I think that whatever E locus gene or pair is being expressed in Bacon, is likely also similar or the same as the ones in Sweet Pea and Ranch, and the same is seen in:
first clutch, fourth picture (silver pullet)
second clutch, third picture (silver pullet)

and maybe in these ones (harder to tell because of barring and/or mottling):
second clutch, pictures 4/5/6 (silver pullets and gold cockerel)
third clutch, second picture (gold pullet)

As I look again at the roosters and the chicks, I wonder if Mayo is Extended Black, with other genes restricting how much black can show. When people cross Buff Orpingtons with Barred Rocks, they get chicks that have one Extended Black gene but show lots of gold or silver in addition, because the Buff Orpingtons are contributing lots of genes that restrict black. Example: https://www.backyardchickens.com/th...que-cross-new-pics.292694/page-2#post-5335507
In that post, see how much gold those chickens have? Yet they must have one Extended Black gene, since it says they have a Barred Rock parent. I suspect Mayo has something similar going on genetically.

Or I also wondered if Serama Rooster 1 might be Birchen, which can produce actual black chickens when it has the right modifiers (increase the amount of black).

I am not very good at sorting out e-locus puzzles. It definitely has a big effect on the appearance of the chickens, but can be affected by some many other things that I have trouble trying to figure it out.