days in Laie, 4 in Honolulu). I would have adjusted our stays almost exactly as you said, maybe even just 2 nights on the south end and the rest on the north shore. Traffic in Honolulu sucks, and it was nice to avoid it when we were up north. But it was good to be there for a few days.
In addition to what you indicated, we loved the beaches on the Windward side of the island. If you can go to Lanikai Beach midweek when there's legal parking - it was a gorgeous beach that wasn't very crowded. We got there early on Friday but had to be gone by 10 AM, which was plenty of time for us. Driving the coast from there back to Honolulu was awesome, so many gorgeous spots along the way.