More criteria for A/B testing

Subject lines are important, but since it is not a valid test unless only one thing is changed, your A/B subject line test isn't enough if I wish to test designs or different copy. Perhaps there is no way for CC to help me make that happen, but I wish there were a way to set up two designs and give the list I want divided into two randomly selected lists so that I did not have to do that on my own. Thanks for the listen!