Beautiful work! The compass looks good to my eye... it does pop off the map because of the finer style compared with the painterly strokes of the map-work, and with the way you've shaded it I'm inclined to believe that you meant to do it that way, plus it matches the border detailing. Yep.

A couple of things I'd probably tweak... Hopefully you're not finished with the SE landmasses, especially cleaning up around the bottoms of 'em. And, it could be my screen... your contrast on the map itself (overall, but esp the SE landmasses) appears hazy and indistinct--like a raw photo of the Maine coast in summer. It might be worth your while to use an adjustment layer with a custom mask to shove the contrast a little more into the clear.

Are you going to put anything into the empty, right corner? It might be an interesting place to place the title.

Oh, and one more thing... the shapes of your landmasses are epic.