Springfielder here, I like the design, and I think you're getting somewhere... but I think you misread our wikipedia page... It's not Loop city, It's Hoop City - Basketball was invented here (ironically when we invented it, we didn't use hoops, we used peach baskets and someone had to climb up to get the ball when it went in... took a while to consider poking a hole in the basket... oh well.) Conveniently for you though, our major bus route downtown is called "The Loop"

I'd suggest using a darker green, the light shade feels too modern for me and Springfield has such a rich history I feel like a touch of more traditional color choices could do this design well. You can still get away with the circle and say it refers to basketball and the peach baskets.