The ocean theme is a great idea (I had sunflowers as a kid and while I liked it, my brothers weren't too impressed). Currently I have a bathroom that has this sort of theme and I found some inexpensive boat postcards and framed them... get more compliments on those than the fancy stuff!
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I shudder to self-promote, but if you're going with this theme some of my cabinet knobs might look really cool.)
Best of luck with your decorating!