My wife and I did the Luau a couple years ago with my parents. It was the first time for my parents, but the second time for DW and I. I liked it as both the entertainment and food were good. I doubt that I'll see it a third time though. The setup is similar to Hawaiian luaus, where guests sit at long tables with other guests, and food is served buffet style. We were fortunate that our table was next to the stage, so we had good seats. I suggest seeing it if you haven't previously.
As for the RPR restaurants, there aren't too many choices: Emeril's Tchoup Chop, Islands Dining Room, Jake's American Bar, The Bula Bar at the pool, plus the Orchid Court Lounge and Sushi Bar. I haven't tried either The Bula Bar or the Orchid Court Lounge, but I've heard good reviews of the Bula Bar. I like both Emeril's Tchoup Chop and Jake's American Bar. However Tchoup Chop is expensive, while Jake's doesn't open until 4pm. I've also dined at Islands, but only for their breakfast buffet, which although good, it is expensive.
Ironically, other than Sal's at PBH, I like RPR's restaurants better than PBH's restaurants. Of course, I haven't tried BICE which is on my to do list. I heard good reviews of Mama Della's, but I was disappointed in the food when we finally dined there. Also, a couple years ago, the breakfast buffet at Trattoria del Porto wasn't open some mornings. Hopefully, they've changed that so that it's open every morning. As for Sal's, they have very good pizza at a reasonable price, and I wouldn't hesitate eating there again.