Billy's on PCH has GREAT fish, it's on the water near Villa Nova and Joe's Crab Shack. I was suprised at the quality of fish they have. Good Opakapaka (hawaiian snaper) is hard to come by in these parts, theirs is great. Ahi there is also excellent. I grew up in Hawaii eating exceptional fish, so there's my par.
I wouldnt recommend Duke's in huntington or the end ot NP pier(neither are a special place).
I cant imagine that Roy's went out of business!! They are a chain, also have several other locations in Ca & Hawaii. I think there are over 15 locations. Not waterfront, but if they're still there...great food and ambiance.