It boggles my mind. I don't understand how you guys can adore the reapers, as a race, but think a human reaper is dumb. Reapers are ALL other aliens + reaper. Harbinger is Reaper + Leviathan. The only thing that is a little weird about it all, is the fact that human reaper looks like a human. That does actually make sense overall, but then why do all the other reapers look like Leviathans? Who knows.
I can understand you thinking it looks dumb, but the idea isn't.