I would probably vote for Hillary over Cruz. Fundamentalists scare me more than lying, career-type politicians (Hillary). Hillary's problem is that she needs Obama in the fall, so she can't really run against his policies. Events like Brussels only strengthen Trump's appeal in contrast to Obama/Hillary's nonchalant attitude toward Islamic Terror. I think Trump, ultimately, is the quintessential pragmatist...which to me is the healthiest way to move forward in this divided country.
For some reason, Trump thinks he needs to smash any critique of him instead of just letting it roll off of his back. Whether he can turn the corner and start acting Presidential or not is the biggest question, IMO. But, if they take the nomination from him and he is very close to the 1237, then I think the GOP is done for the next decade. The base will punish the establishment over the next several elections. That would not be healthy for the country. After all, the right has ordered this situation up after years of letting talk radio dictate politics. They need to let it play out.