I'd offer an extension to Johnny K., I think that he is good enough and has earned the right to stay (if he wants to).
I really like Nicholson, decent footballer, great personality, but quite injury-prone. He's 50/50 for me.
I had hoped to see Robinson get some games to see how he might fit in with JBA's style of playing, but, sadly, he may not get the opportunity to prove himself. The other free agents can leave with thanks, they've all played their part.