His biggest obstacle to getting his nominees through the Republican-controlled Senate is simply that he hasn't even bothered to nominate anyone. The only appointees at issue are a handful of super-bootlicking, especially unfit lickspittles who are so awful he can't even get Moscow Mitch's Senate traitors to approve.
I personally know over 100 people that could do Trump's job better than him. I think perhaps even I could. Unlike Trump, I would heavily lean on all available resources including experts and my advisors to minimize my presidential weaknesses.