I don't think he's overrated because when I saw him with Miles a couple of times in 1982, he was stellar. Once he started producing and getting into more straight fusion stuff, I found him to be boring, but I know he has tremendous range and imagination in there somewhere. The grooves on The Man With the Horn (especially Fat Time and Back Seat Betty) and the raw jams on We Want Miles were exceptional at the time. After that, so many people copied that style so it became cliched and pedestrian. But he was breaking ground back then and that's not something achieved by many of those who came after, including the bassists who followed him in Miles' bands.
I feel the same way about Mike Stern. Seeing him with Miles and then in the small clubs around Boston in that era was a powerful experience. He went a bit off the rails, hanging with Jaco, but then sobered up and while he's a good player, I've not heard anything like the fire I saw during the early 80s. Although on a personal note, I'm glad he got sober and didn't suffer Jaco's fate.