The 'DON'T' message Midge wrote to her future self and didn't understand when she reads it, is latter explained when Gordon's wife tells her 'Don't', as in "Don't give away what's yours".
When asked if she likes her career, Midge says if she could do anything else she would: "I'm talking dry cleaners to the Klan, crippled kid portrait painters, slaughterhouse attendant". This is what Lenny Bruce says to Midge in season 1 episode 2 when she bails him out of jail and asks if he loves his career.
The scene in which Tony Shalhoub (Abe Weissman) has drinks with his colleagues and reflects on his children, he is reunited with his Galaxy Quest costar Patrick Breen (Quellek).