I don't think my Define case is heavy, despite components or the metal structure. Or rather, it doesn't feel heavy because it's a comfortable carry. It is not a case I'd appreciate carrying handles. A lot of the time, they look tacky (Vengeance C70, the tacky of all tacky cases), but on some, they are absolutely necessary.
I'd prefer the carryingstyle I can use with my Define, lean it to chest, hold under/side, and you lift it with the whole body. It wouldn't work with heavier or bigger cases, so I can understand why some do have it, since no other way works. /shrug