I'd say probably easter egger. I've had all easter eggers and all buff orps. No complaints about either, but I like variety (which is why I now have a mixed flock). The easter egger choice gives you the variety in appearance, but fits your one "breed" criteria. I didn't read the whole thread, so not sure if you gave a reason for only wanting one breed, but if there's not a good reason for it I'd suggest a mixed flock. The difference in the birds and the eggs is fun. I have a couple of easter eggers, a bunch that lay varying shades of brown and one white leghorn. They all look different as do their eggs. It just adds a lot of variety.