Another thing I think would likely happen if "profit from likeness" goes into effect is that the 501c3 status of the NCAA and the athletic departments, which is already under scrutiny, would come under more severe scrutiny.
I think it would be pretty easy to prove that the NCAA/AD facilities, resources, and exposure, in the vast majority of cases, help to create the image that would be profited from. Generally, the resources of a 501c3 can't be used to create monetary benefit (other than salary) for those inside of the organization. Apart from changes to the non-profit tax law or making the athletes employees, IMO, "profit from likeness" would pretty much make the case for a 501c3 revocation. Whether this is good or bad is another debate.
Furthermore, many ADs are not fully self-supported, but receive tax money from their schools to operate. Using tax dollars for facilities that help individuals within the organization receive monetary gain gets into more gray areas and probably violates laws in many jurisdictions.