I have 2 babies that hatched today (little mutts from my Silver Laced Wyandotte rooster and the hens are: Australorp, Buff Orpington, Partridge Rock, and Lt Brahma) and they look exactly like your first little dark ones! black on top, white on wingtips, throat, belly. Mine have a couple of tiny white splashes the face--
my first little grand-mutts! ;0) The eggs were from the very first week or so that they were laying-- I knew the rooster had been 'roostering' so this was sort of an experiment to see if I could get good babies and YAY! they are wonderful !!