I think you can't go wrong with any of those three casual seafood spots.
That said, Solu at The Resort at Singer Island is phenomenal -- they serve Asian-Caribbean food that's delicous and unique, and the modern dining room overlooks the ocean. My favorite seafood dish there is the coconut curried snapper. The shellfish hotpot with chorizo and teriyaki salmon are also amazing!
I had a wonderful brunch experience a few weekends ago at Solu (at The Resort at Singer Island) -- I enjoyed a delicious lobster omelet and my boyfriend had the breakfast quesadilla with avocado and some yummy cheese. We both ate everything on our plates!
Love the inventive combinations here, and the ocean views are the perfect way to start Sunday morning. Prices really aren't that high, and the ingredients are so fresh and feel good. Definitely try brunch at Solu!