Your editorial proposing an overhaul of UC to improve its undergraduate education makes a valid point, but it also contains a major fallacy it seems to me.
Valid point: It's true that many undergraduates do not thrive at a mega-campus like Berkeley or UCLA, which does indeed argue that some or even most of the other UC campuses should stop growing when they reach 20,000 students or so. Given the apparent reality that enrollments will continue to increase, this implies in turn that a 10th campus may be needed.
On the other hand, judging from my own experience (almost 20 years as a professor in the UC system), there are a couple of serious flaws in your notion that the smaller campuses should change their "hiring and tenure decisions" so as to emphasize teaching at the expense of research.
First, the step you advocate is unnecessary, because research and teaching are not incompatible. Far from it: At an institution of the stature of a UC campus no professor can be an adequate undergraduate teacher unless he or she keeps abreast of his field, which is done by closely reading the current literature (mainly, journals). How can someone with an active mind read closely without reading critically, or read critically without seeing things he can mend?