50% seems insanely low given the details of your situation and injuries/disabilities. I would strongly encourage you to consider hiring a firm to assist you through the process to gain the appropriate level of compensation you deserve. I used a company called Vet Comp & Pen Medical Consulting, LLC that was recommended to me by a fellow veteran and they were able to achieve what a VSO or myself were not able to accomplish and got my rating increased to % I felt was much more accurate based on my conditions. Its not free but they only get paid if they get you an increase on your rating. They know exactly what they're doing and make the process much easier than trying to submit and do everything on your own. Check them out, its worth 10 minutes of your time and you only have everything to gain.