My personal views only:
1. your night shots are stronger than your day shots. Maybe the reason is that the night shots force you to crop out or ignore, more of the distracting stuff (that is of course, more visible in the day time).
2. you should not be afraid to have people in your pics (model releases etc. advice you need to get from someone other than me)... for instance, who handed you the pink heart with the message on it? If the blinged-up H2 could have been shot with "Dr. G" standing beside or in front of it (or even his driver), that could have made the photo more interesting.