What would have happened, if Trump was assassinated?

Who would have replaced him, as the republican candidate?
Would his supporters start riots?
Would everyone actually be unified, by such a tragedy, like after 9/11?
Would all Trumpers, still vote red?
Would you consider it a good, or bad thing?
How would no more Trump, affect our pathetic republican led congress, if they don’t have to always please Trump?
How would the world react?

ATTENTION. I would prefer serious contributions. I didn’t want a thread to be another Trump beating, echo chamber.
And please be respectful as possible, as this was very close to actually happening.
What would THIS new timeline be like? Like in the universe Trump did die.