Amador, you forget these weapon skills are not job specific. So therefore these weapon skills are not meant to replace things like Ukko's Fury, Drakesbane, Stringing Pummel. Stardiver is meant to give Drakesbane-like power to other Polearm wielding jobs or to even the disparity between Drakesbane and all other polearm WS. If Stardiver were a job specific weapon skill, than it would be a different story.

Also, if Stardiver was stronger than Drakesbane, don't you think SAM and WAR would hop on that bandwagon and start using Polearms? I can guarantee that if Stardiver outdamaged Drakesbane, WAR and SAM would make better use of it than DRG since WAR has Berserk/Hasso/Bloodrage/DA and SAM can spam TP like crazy.