hi,
I'm by no means an expert but AE reds in front and AE greens in the rear seems like a very unbalanced setup. Especially with a rear-heavy car like the sprint 2.
Not sure what tyres you're running but blue/ blue or maybe even Gold rears / blue fronts would seem better. Maybe blue rears / sliver fronts for something softer overall ? just my 2 cents.
Also, regarding the lead in the bumper, I've always been told that any weight past the wheel axles (overhang) is bad for any onroad car.
Nice job on the tensioner BTW, though not adjustable it is simple, efficient an clean.