He only took Priebus to try and link to rank and file Republicans, because Priebus was the chairman of the RNC. Trump's just greasing the skids to get someone else in there more amenable. Might be tougher today as his first choice washed up on a riverbank in Missouri last night. 

Flynn was just taking orders from Trump who was just taking orders from Putin. He's having a tough time firing him even though he got really caught *really* early.