For Berkeley, Clark-Kerr will be by far the best dorm in terms of layout, but it is a 20 minute walk to the center of campus (or a few minute bus ride). Bowles looks like a castle from the outside, but never been in it. It has a separate application process from normal Cal Housing. Blackwell is the newest dorm, just opened up last year, and will be very close to the buildings in the west and center of campus. Foothill/Stern will be closer to the STEM buildings.
My kid is in Blackwell this year and just renewed for next year as well. I think the main reason why he likes Blackwell so much is that it’s literally a few steps from the main student gym (RSF) which is an awesome and gigantic place, to relieve the stress after a hard day of classes and studying.
Also, to me a slight advantage of having spread-out dorms in different areas rather than in one area is that it matches personalities better. Foothill has always been the more quiet area, while the Units and Blackwell are more considered to be social dorms.