Just found something rather interesting on another site about why we never got anything before Hallelujah Land:
"In regards to their release of the Bobobo-bo Bo-bobo manga, they said the decision to not start from the beginning was actually at the request of author Yoshio Sawai."
Why the heck would Sawai not want to release the first part of the series? As inconsistant as parts of that was, a lot of it was classic! (including the entire Gunkan arc, the Z-Block arc, the fight at OVER's Castle, even some of the stuff regarding C-Block and A-Block!) I really hope somehow it gets overrulled and we get the early part of the series eventually.