I used to have the same problem with going slow. My coach told me I needed to work on my "emotional control". I think she had a good point.
I dont know what atlanta looks like but hill repeats are the way to go if you want to build some good cycling specific speed and strength. Find the steepest hill you can and giv'er. Repeat three to five times depending on the length of the hill.
Funny, a life time of cycling and thats the best advice I've got.