I JUST did this very thing! I have 2 Silkies and a Sebright that are about 3.5 months old. I just integrated them with my 5 large breed hens. I brooded the bantams in my house for a long time (longer than I wanted). I was really worried about the Silkies getting picked on. But that isn't what happened AT ALL. Let me explain what I did:
I expanded my covered run (it's over 200 sq ft now) and fenced off an area of it to keep the bantams separated from the big girls - the "see each other but no contact" method. I also let them forage all together in the yard (VERY closely supervised) every day. There weren't any problems because the big girls ignored the babies for the most part. This went on daily for 2 weeks or so.
Then I made small openings in the fenced off area of the run so the bantams could go in and out as they pleased. The openings were too small for the hens, so the bantams had a safe place to retreat.
Well, right away, the bantams were out and about with the big girls. Within a week or so, they had demonstrated that they are not even at the bottom of the pecking order - my poor Welsummer is! I now have one flock of 8 birds. They have disagreements every once in a while, but nothing beyond the occasional peck and flapping of wings. Surprised the heck out of me, especially since I have 2 hens (a BPR and a Brahma) who can be bullies. My Silkies have no problem sharing the run with them.
I was so worried about integrating them after reading all the same horror stories you probably read that I decided to build them their own separate coop. But now, I don't know that I needed to do that, tbh. No biggie, though: I now have a grow out coop or a brooder or whatever.
DISCLAIMER: My Sebright is a sassy cockerel, and he is pretty darn protective of the Silkies. I don't doubt that he has made it much easier to integrate the Silkies.