Meh, I disagree. CS 188 is not a very useful course. You can learn 188 material very quickly (i.e. reading Wikipedia for a couple hours) if you do well in CS170 and CS 189.
I think for data science: Stats 134, CS 189, EE 127, EE 126 are most useful (in this order). Of course, in order to do well in CS 189 you need to have a good background in probability which can either be CS 70/Math 55 (if very well understood), or Stats 134, or EE 126.
I personally thought Stats 134 was the hardest of those courses by far (though I took it under a visiting professor who was needlessly difficult). 188 was a breeze, and I believe the full course is offered for free on edx
I think for data science: Stats 134, CS 189, EE 127, EE 126 are most useful (in this order). Of course, in order to do well in CS 189 you need to have a good background in probability which can either be CS 70/Math 55 (if very well understood), or Stats 134, or EE 126.