The music is great, the feel of driving around is wonderful, the city looks wonderful. I think it would be nice to have an arrow or something pointing to the location in the overworld, so you don't have to just watch the mini map so intently. Another improvement could be having it be clearer when the next order is going to start. Sometimes it felt like the order would start right after the last, other times it wouldn't start until I actually dropped off a pizza.
Either way, this game was so much fun, drifting around to the synth music is a blast!