I don't know how many breeds of chickens I've had over the years. Lots. I've liked them all, more or less, and can't recall any that I simply would never have again. There are some that really stand out from the crowd, and will always have a place in my flock.
Red / Gold Sex Links - I know they are not actually a breed, and that they are different from each other to boot. But they are similar enough that I use them interchangeably. The first ones I got, forever ago, I ordered 2 red sex links from a hatchery, and received one, with a gold sex link substitution for the other. That worked out well, and continues to work out well for me. I like both and I like to have both for the visual variety. They are great layers of big, brown eggs. And they are just nice birds in general. The smartest hen I ever had was a gold sex link, the one that acted like my dog was a red sex link, and so on and so on. Really, favorite birds. Big, healthy birds. I haven't had any problem with them "burning out" early, or being unhealthy in any way. I have 2 big, older red sex links now. I'm not sure how old they are. Maybe 4 years old? One of them is the head hen. And I got 2 gold sex link chicks a month ago. Guaranteed brown eggs in the basket, check. Sex links. Gotta love them! (I've never had brown or black sex links, maybe I would love them too.)
Easter Eggers - Again not really a breed, I know. They are such awesome birds! They make up the majority of my (adult) flock right now. It's funny, folks around here are suspicious of the blue and green eggs. They don't like them. I like them just fine, but the eggs aren't the reason I like the birds. The birds are just cool. I like the wild-type plumage, the way they look like they just wandered out of the woods and decided to hang out in my yard. Each one is different, and has a subtle beauty. (I have both bearded and clean faced girls, and I like both, with the clean faced maybe a little prettier to my eye.) They are sweet birds. They don't necessarily like to be held, but they are easy to handle when handling is necessary. They lay lots of eggs also. And they are always interesting to breed. You come up with lots of lovely, unique chickens when you hatch easter eggs.
I don't have any Buff Orpingtons at present, but they are super nice birds. The ones I had in the past were big and fluffy and totally friendly. They were excellent broody hens, and I would like to have one just for that purpose. The downside was that they seemed to suffer more in the summer heat and humidity than some other breeds.