I disagree with your assessment, BRTD. As long as Rubio stays in, the more likely he deprives Cruz of critical wins in WTA states. Cruz actually does quite well against Trump 1-on-1; Michigan exit polls had him 43-41, with the rest choosing no one. I think Cruz would easily beat Trump pretty much everywhere west of the Mississippi in a 2-person race, even in California.
There aren't many actual WTA states though. The only big ones are Florida (which may be a lost cause) and Ohio (where Kasich is clearly strongest.)
