The Master Suites are only in building 5, by the cascade pool. They are not ocean view. They are bigger, with a separate living area.
Excellence Suites are ocean view, and they are also bigger. They also have balconies facing two ways.
Building 10 would be my preference. It is Club only though. Building 6 is not good for ocean view, as it looks out over the swim-up bar, Lobster House, and the Grill. Part of 7 is the same. 14 is beside the flea market next door. 11 is fine for non-Club. 2 and 3 are non-Club with nice views on the cascade pool side.
Is it worth upgrading? That's a matter of personal choice. I don't. I find the regular rooms quite nice and spacious, and I don't spend that much time in my room anyway.
Here's a link to the rooms: excellence-resorts.com/guest-suites/suites-a…