It should be obvious that H-1 is not enough to connect west and east on Oahu, especially with growth in the "Second City" and points west. H-1 will be (some days it already is) overwhelmed; you can only build so many more lanes.
A look at a map of Oahu shows that another route exists from west to east.  The route follows Roosevelt Blvd. to Geiger Road, across the Eva Plain to Bravo  Rd., tunnel under the Pearl Harbor channel to link up with South Ave.  leading to Nimitz Hwy. and the Viaduct. Most of the route has existing roadways with enough right-of-way to build a freeway. 
If the goal is to relieve traffic and prepare for the future, this is what is needed.