I got into all three of these UCs for a Computer Science Major.
Davis:
Pros:
Near Valley
Near Home
College Town Feel
Cons:
Not known for CS
Smells sometimes
Irvine
Pros:
Known for CS
In LA (very nice location)
Dedicated school for CS
Cons:
Commuter Campus
Not Near Silicon Valley
Bad College Experience
Santa Cruz:
Pros:
Awesome location
Cons:
Not as prestigious as UCD or UCI
Congrats on the acceptances!
UCSC might be great for CS. My cousin went there and its proximity to tech companies is a huge advantage. Sure, there’s also Stanford students in the mix, but lots of CS majors from UCSC are able to get jobs at great companies 
My cousin bounced around quite a bit. He started at a small startup company. Then he went onto Google and worked on the camera tech for Google Maps. Most recently, he’s working at Apple. My vote would be for UCSC, but what does your heart tell you? UCI isn’t bad either. Some of my CS professors at USC did their undergrad at UCI.