Thats what I was thinking of doing, take the biggest offspring of each cross and cross them together. The result should then be big enough to start getting all the silkie features bred into it. Plus using Orps and brahmas widens the genepool.
I've been reading through this thread, and this project is so cool! I might try this myself, though the breeds I have I'd be crossing is buff brahma (pretty sure its a cockerel) and two buff orpington pullets. I have a silkie roo thats pretty big, so I think I might cross silkie roo x orpington...