He fired Comey. And he terminated the search for the new FBI headquarters. So I'll give him credit for that.
He should had not gotten rid of Steve Bannon. He needed him as his gatekeeper. Michael Flynn may had been another potential gatekeeper but the Deep State got him.
And Pence got him. Maybe I’m being redundant.
On the top of my head, the way to shake-up the FBI and DOJ is to rotate all senior divisions, (lock, stock and barrel), to the field offices around the country and replace them with agents and lawyers from the field offices. This allows you to put more qualified, loyal agents/lawyers in the decision making slots and removes the “snakes”, (Ohr et. al.).
Also fire or transfer all SAC’s and ASAC’s which changes the politics in the offices.