Actually, there are plenty of good reasons for Native Hawaiians to oppose the Akaka Bill, from believing that it’s not good for Hawaii to mistrusting how it handles the creation of the new Hawaiian government.  But the reasons don’t have to be specific to the bill itself.  There is also a principled approach that questions how it affects the Hawaiian spirit of ohana.  Consider this explanation given to Grassroot Institute President Richard Rowland by a Native Hawaiian who is concerned that the Akaka Bill forces Native Hawaiians to turn their backs on spouses, in-laws, and friends:

In addition, they would also be turning their backs on many others with whom they might have long and close ties that bind such as:  hanai children or parents, aunties and uncle, classmates, teachers, students, coaches, business partners, co-workers, faithful employees, squadron mates,  church parishioners, canoe club members, swim club members, fellow professionals and on and on.

The Akaka bill allows only those with at least one ancestor indigenous to the Hawaiian islands to participate in the process of creating the new government; but it leaves it up to the new Native Hawaiian governing entity to decide the criteria for its own citizenship.  Since the Akaka bill is intended to protect the existing race-based entitlements, it is a given that the new government will not have an Equal Protection clause.  That means the new government will be free to discriminate on the basis of race, even against some of its own citizens.

Hard to see why any Hawaiian would want to join.