Honestly, I don't think it'd suit Zoro's character. In the same SBS, Oda mentioned how Luffy and Zoro don't really talk about the past.
They're not ones to dwell on what's happened, so Zoro all of a sudden basing his lifelong dream on revenge due to childhood trauma seems a little out of character.
Plus, would it be nice if Zoro had a decent backstory plotline? Yes, but ultimately I don't think Oda cares enough. It'd be great if there was something though.