As a further addition to my thoughts: the simple fact of the matter is since the "Default" map is hand-drawn it will never be terribly accurate. It's really just that simple. The "North King" version is a big improvement over the "Jason" one, to be sure, but it still uses the Jason model as a base, and therefore will carry all the flaws inherent too. The only way you're going to make it much better is to redo it from scratch, and there's no need to do that when you can just take one of the two above.
I know I got fed up with the Jason version when trying to place cities in stSKNES5 and I've championed greatly accuracy ever since. I have to give NK due credit for improving the map by leaps and bounds but that map's strong point in my opinion is ease of use, not accuracy. A machine-generated Earth map, or one produced by a cartographic agency, is simply going to be better than any that we can draw by hand in representing accuracy. If that's your goal, there's no reason to stick to the current map or modifying it very much at all, because it's never going to be all that satisfying in that particular realm.
Of the two, the larger tends to be better, simply on accord of having rivers already placed, although it's rather easy to add them to the other one. On another note, if anyone wants "spiffy" blank versions of either of those two maps, I could generate them fairly quickly. Might do so for fun soon anyway.