No, I say leave it. it's more "recognizable"
Hey Delta if you have time (and thanks if you do!) can you remove the hinomarus from the Ki61 wings, and the star-and-bar from the f4u wing? There's a star and bar behind the plane, and there's a rising sun behind the ki61, and in consideration of how small the detail on the Karelia patch, I wonder how it would look with simple black silhouettes and white outlines.
I agree that the white outline will probably look good, even if it's a small detail. The outline on the Karelia patch kicks arse, I bet this one will too.
EDIT: I mean try this just so we can see, not to make the final like this (not yet)
EDIT2: Would it be possible in this "test-try" to make the water darker (or a different shade of blue) to differentiate it "just a tad" from the star-and-bar?