It looks like “slow feathering” more often affects males? Is that right?
Not as far as I'm concerned. There are differences in how males and females feather out, but this is during a juvenile molt at around 3 to 4 months when the boys grow the saddle and hackle feathers, things like that. That's not what you are looking for.
I think where that comes from is feather sexing. If the mother has the dominant slow feathering gene and the father has only the recessive fast feathering gene their daughters will only get a fast feathering gene from their father and be fast feathering. The boys will get a recessive fast feathering gene from their father and a dominant slow feathering gene from their mother. Since slow is dominant they will be slow feathering. There are a lot of myths and misunderstandings about feather sexing, I can easily see where all or most boys are slow feathering could come from that.
Hoping to limit how long they need to be indoors, so faster feathering would be preferred. Does that mean I need to avoid certain breeds entirely? Or just if I were getting males?
Funny you should ask. The first post in this thread explains how genetic sex linking works and chart #3 in that post mentions certain breeds that are typically fast or slow feathering.
Sex- linked Information | BackYard Chickens - Learn How to Raise Chickens
I'll copy that chart.
I consider the difference in fast or slow feathering isn't worth worrying about whether a broody is raising them or if I'm raising them. The difference isn't much, the weather is so variable, and we are typically so cautious about it that it just doesn't matter. You are in Georgia so you won't be that late in the season. I think the other characteristics of the breed are much more important than fast or slow feathering.
If your concern is getting them out of your house as soon as possible we may be able to help you put your brooder outside. In Northwest Arkansas in a climate a little cooler than yours I'd hatch chicks in late February and have them off of heat by early April at 5 weeks old. My brooder was in the coop so it was easy to acclimate them. Mine had Sussex, Orpington, Australorp, Rock, and Delaware for parents, all slow feathering.
Sometimes it helps us come up with a solution if we know what your real concern is. I could be wrong about yours but if getting them out of the house is it I think you have better options than worrying about breed.