I think a good approach to potato salad is to have what I might call a "theme," a direction for it to, so it has accents that work together and doesn't become a muddle. A lot of people like their mayo type to go herbish, mainly dill, including both the fresh herb and the pickles. A prominent vinegar note goes well with that, a light, sharp vinegar, rather than a heavier balsamic. I see a lot of them that use too much mayo, and I think they become too much a chunky cream, and that predisposes toward a blandness that is hard to counter with other ingredients. It's a POTATO salad, a salad of potatoes, so it shouldn't drown in it's "dressing." And if it seems blah, a touch of Louisiana style hot sauce isn't out of place.
Oh, And everything's better with bacon. Right?