Scott Adams makes a strong point: if you're losing, you need to take chances if you want to win. You can afford to play it safe when you're in the lead.
Do you want more risk?
Generally speaking, you want to avoid risk when things are going well and accept risk when things are totally broken. If you think the country is doing well, and will continue to do so, Hillary Clinton is an excellent choice on the left, as is Marco Rubio on the right. They will keep things mostly the same.
But if you think government is rigged against your interests, and unlikely to improve on its own, you want a bloodless revolution. And the candidate you hire for the revolution is likely to have rough edges.
Still, I think I prefer Tex Cruz, the less erratic antiestablishmentarian. I disavow all of Trump's racist, xenophobic, crazy remarks.