The Alex I just shipped you uses the "paint gridlines over the surface of the map" method. I also considered the "separate blocks" method, but discarded it as rather more work. My sense of aesthetics is disturbed by the concept of losing a pixel every 48 or 54 - but what do you think of the result?
The advantage of this method is that the code is localized to one routine, and is almost ridiculously simple. With the "separate blocks' method, I'll have to touch about half-a-dozen different functions, and will have a bit more complexity to deal with. But if you feel strongly about it, I'll do it.
As a compromise measure, I tried drawing just crosshairs in the corners of the 3x3 cell blocks (my crosshairs extended out 3 pixels in each of the four directions). The results were so disappointing that I probably won't bother to pursue that idea any farther.
I'll gladly share the "blame" for the smoothing algorithm if I can share the credit for the world-generating algorithm, which I still think is delightful. How about doing some sort of curve-fitting to smooth the edges? What do you know about bezier curves?
Anyway, the good news is that if you don't have a smoothing algorithm ready for me, I have more time to work on the mundane stuff - like bug fixes.
Thanksgiving will be at the Walker's this year, as usual. Friday I'll be back home, so I should have a couple of days to work an Alexander and (maybe) get Archipelago out the door. What are your Thanksgiving plans? How's the Newton?