We all have different preferences and priorities in travel. Some are willing to take a preferred airline between A and B even if it involves a connection or poor timings. Others will argue that whichever airline offers nonstop service at convenient times is the preferred airline. Based on your statement about preferring SJC and nonstops (not to mention Hawaii) you may want to pick Delta. But take a look at the scheduling alternatives between DL, UA, and WN, and check both SJC and SFO, to decide which airline's choices seem reasonable to you.