Silkies do come in standard and bantam... though I believe the standard (or LF) are much more the norm in Europe, there are a few folks in the states with them...I have crossed my Silkie with a LF rooster hoping for some larger broody types, but so far they are tending to stay about the same size as mama... time will tell with the last 3, since they are about her size at 17 weeks, so they may end up slightly larger.
For larger broodies though, I have had great luck with my Silver Pencil Rocks and even had a hatchery Black Giant... so if they continue that trend I won't need to worry about having banties for broodies.
The little ones sure do seem lost the first few days... hard to not coddle them when it happens, but they will find their place in a short time. Our current Black Giant broody is now taking her 6 week olds up onto the roosting platforms (3 nights now)... they all get to cuddle around her, but are in the midst of all of the bigger birds also. During the day she is still taking care of them and today had them in the woods digging through leaves. I think she will be ready to leave them within a week or two though.
Yes, I could tell at around 5 weeks she was going to leave them, she would go off and scratch for a time by herself and then a week before she rejected them the roo started mating with her again.. It didn't surprise me when one night we heard a commotion (the henhouse is at the back of our property about 3/4 of an acre away) we went out and she was pecking the heck outta a few of them trying to get away from them...