The biggest problem with government for economists (and ultimately for people) is how incredibly inefficient it is. I have always loved the idea of bringing private sector efficiencies to the public sector, but before this there hasn't been anyone who has had the ability to effect change like this. Reagan probably came closest since he had done wonders in California, and was a small government guy at heart, but Trump has great potential from that perspective. From the big government perspective he also has the ability to know what factors are a catalyst for small business and large businesses and because of that private sector confidence is through the roof.
Obama, love him or hate him was a failure at spurring on business. He will forever be known for his creation of the "jobless recovery." Translation: "I have no clue what I'm doing"