I was able to use voc rehab when i was only 20% service connected myself. If i remember correctly one of the major deciding factors was basically the need for re-training into a different job. For me before the USCG most of my work was security which involves prolonged periods of standing. My knee was injured in the USCG to the point where prolonged standing is very painful.
I think one thing that will be important for you will be for you to look into different career arena's and try to find one that will likely work best with you to minimize the issues that you have. It seems in many ways that a job that allows you to primarily work from home would be the way to steer. You know you best though, i would simply say to build a case on a career field that will play to your strengths the most and look into what degree path will be best. You can also explore possible certifications. I went into networking myself. So I got a bachelors in networking and to make myself more competitive i got a network + a security + and a ccna cert. It helped me get the job i currently have in networking.