Get rid of the GI Bill, or at the very least, tie it to the draft. As in, you don’t get post service benefits unless there’s a draft going on. Otherwise you just volunteered.
Then, provide those same benefits we provided since 1944 to the legal and medical professionals. Kids enter into service at 18-20 and come out as public defenders, nurses and doctors, where they are subject to working in poor areas to help the underserved.