I had the same DPE for both the private and instrument rides. I'm pretty sure at least one maneuver during my private ride (maybe steep turns, can't remember) was not up to my standards, and one of my ILS approaches was probably safe, but sloppier than typical in my training. In both cases, I recognized that these maneuvers were not the best, and explained why I was dissatisfied to my DPE. I think you you fly a bit sloppy and don't recognize it, it is not a good sign of good future decision making. Fortunately, I was up to standard for everything else on my private checkride, and I positively nailed a partial panel non-precision approach (I always like flying partial panel anyway), so the DPE was happy with my overall performance in both cases. I don't think it is reasonable to expect pilots to be perfect, but it is reasonable to expect them to be safe and to recognize when things are a little off.
My wife had the same DPE, and for her private, she was asked to plan a route to Groton, CT from Central NY. When she presented a rather non-direct route, the DPE critically asked her why she planned a route so far out of the way. When she replied she was not enthusiastic about flying over the Catskills where there are few emergency landing options unless absolutely necessary, he was suitably satisfied with her reasoning and she went on to have a nice checkride.
Bottom line: Fly like you trained, and go with the flow. You should be well-prepared to meet standards. If you do something not up to your standards, explain and own up. You will probably do just fine.