This wasn't the worst coaster I've ridden, but it certainly wasn't the best!
Firstly, little things like the station track not being straight (just select the segment and press 'I') and the uninspired layout didn't really get things off to a good start.
The track was pretty jerky in the transitions and there was some pumping around some of the corners and hills. Also, the forces just didn't feel right. They we're consistent enough throughout the track.
Also, like Snoo said, there were too many supports for quad-track. I know you say that you always over support, but it's really poor practice to do so. We're aiming for realism with the final output and to be honest, just packing the supports in there isn't realistic.
Overall, you're learning, but there's still a way to go!