Oahu (especially Honolulu) reminded me of California given how crowded and dense it was on my four visits. I haven't been back since the late 90s. But it has some amazing restaurants and the North Shore was far less congested.

I've heard Maui is the compromise between the hustle and bustle of Oahu and the slower pace/less developed islands like Kauai or the Big Island. Hope you get to visit Maui soon!