If Trump really truly does go independent policy wise. He'll need to court Democrats, that's going to be interesting. But it will cost him the Freedom Caucus for sure, those guys are ideologically rabid.
Also say what you want about the WH, but John Kelly has been good at distilling the crazy policies from the WH into workable action. Look at the Muslim ban for example, Miller and co crafted crazy EO policy and then Kelly still managed to blunt by pushing for Green Card holders to be exempt etc.
He's in charge of one of the most important Secretary positions and managed to remain relatively unscathed. (Trump Admin Standards)
Basically I'm not writing this off and expect a complete clusterfuck. Russia investigation will be the real wild card.
That is what will make Trump truly unhinged. If it escalates, alienated GOP might push for impeachment.