Oahu welcomed us kindly. Though hotels are common in the area, I'd highly recommend an AirB&B — much cheaper. Further, all beaches that we came across were public, so there is no loss in coastline.
Lahaina was a beautiful small town, full of art and views. Though most of the galleries are extremely boujee, they were welcoming to those who clearly weren't going to buy (I strolled in sandals with a frisbee to a gallery whose average price was probably around $5k). If on Oahu, I'd also recommend getting a PADI license (it took only two days for me) and specifically the Lahaina Luau.
On the big island of H'awaii: I wouldn't recommend. It's large and beautiful, but mostly empty beyond a large airport.