Never having eaten at FF I would say bluezoo is worth a try. We went last spring and our experience was mostly good. Here's the good, bad, and downright ugly.
Good: the decor and atmosphere are very quirky, yet refined. The Dolphin is largely a convention hotel, so the guests are mostly business people. Yes you'll see kids there, but not likely as many as FF. The wine list is extensive, and the server we had was good at making pairing suggestions. The food is fresh, fresh, fresh. It tastes like it was swimming around just this morning. Try the seared scallops with braised shortribs appetizer. I guarantee you've not had better scallops - crisp and brown on the outside and creamy on the inside. Not a trace of fishiness. The Citrus Five Ways dessert is truly unique and delicious.
Bad: we went on a Thursday night and the service was still slooooowwww. I realize that one should expect a slower pace in fine dining, but it took the two of us almost three hours to finish our meal. In spite of the above wine pairing comment, our server was largely indifferent.
Ugly: two words - Dancing Fish. Run (or swim) away. The presentation looks spectacular when you come in the restaurant. A skewered whole fish turns at a 45-degree angle over the fire. I was sold instantly. Unfortunately, it remided me of everything I hated about eating fish as a kid. The flesh (Chilean Sea Bass) was tough and flavorless. The server mangled it at tableside while trying to remove the bones. I spent the rest of the night pulling bones from my mouth. This was almost enough to make me never return.
Return we will, though, and we'll hope for a better night. Besides, I'd crawl on my hands and knees through a nest of cranky scorpions to have that scallop appetizer again. We'll try Flying Fish first, but someday we'll be back to bluezoo.