Trump is trying to bring two factions of the Republican Party together. The Bannons and Sessions represent his hardcore base that want border security, law and order, and an end to "PC" language. Priebus, DeVos, Haley (and potentially Romney) are establishment Republicans. Although he ran against the establishment, he's also aware that in order to actually get anything done he has to work with them (especially since Republicans control both Houses).
Finally, the choice of Carson as HUD Secretary is sending the message that the plan to help inner cities was not just campaign rhetoric. Let's hope he delivers.