Did I lose you at blue cheese?! I always assemble the Cobb salads on individual plates sans blue cheese and then let my guest (or children) decide whether or not they want to top theirs with blue cheese.
If you are not a fan of blue cheese or just haven't yet been brave enough to give it a try, you can make yours without the blue cheese and I promise not to be terribly offended!
Now that we've cleared up the blue cheese argument, back to the quality ingredients! Buy produce that is in season if possible and as fresh as you can.
If you can't find that dressing or are looking for something milder, other common dressings for Cobb salad include blue cheese dressings or avocado dressings. Of course, you can make your own dressing and for many of my salads I do, but since this salad is one that I make whenever we are on vacation, I try to keep it as simple as I can and dressing out of a jar is one way to achieve that.