Trump is absolutely more of a political unknown. But he has great leadership and media skills and is obviously a traditional patriot.
Trump and Hillary will be the nominees. Cruz...and the rest of us...need to make peace and give Trump the ability to win from the right.
The rush to pre-empt the primary process is suspicious to me.
If Trump realizes the necessary delegates by June, that is plenty of time.
I suspect Trump supporters know that Cruz is more of a threat than they want to engage.