[Wikipedia-l] Colors for maps

[Tomasz Wegrzanowski]

http://meta.wikipedia.org/wiki/The_polygon_map

Political maps use 2-level coloring schemes.
Main color is selected as to avoid 2 neighbour countries having the same color.
It's shade is selected randomly.

The problem is to select such N (N about 8) colors generators,
and such colors for seas, rivers, city and country labels,
and other objects (borders, river/mountains/island/sea labels etc.),
that makes maps most readable.

Currently used scheme is:

Colors for:
    city dots		white
    city labels		white
    rivers		#000060
    seas		#000060
    country labels	#FF8080
Color generator 0  # cyan
    $r = rand 64;
    $g = 160 + rand 64;
    $b = 160 + rand 64;
Color generator 1 # green
    $r = 64  + rand 64;
    $g = 160 + rand 64;
    $b = 64  + rand 64;
Color generator 2 # yellow-green
    $r = 128 + rand 32;
    $g = 192 + rand 64;
    $b = rand 32;
Color generator 3 # greenish-blue
    $r = rand 32;
    $g =  64 + rand 64;
    $b = 128 + rand 64;
Color generator 4 # yellow
    $r = 128 + rand 64;
    $g =  96 + rand 64;
    $b = rand 32;
Color generator 5 # orange
    $r = 128 + rand 64;
    $g = 64  + rand 64;
    $b = rand 64;
Color generator 6 # magenta
    $r = 160 + rand 64;
    $g = 64  + rand 64;
    $b = 160 + rand 64;
Color generator 7 # gray
    $r = 96 + rand 64;
    $g = $r - 16 + rand 32;
    $b = $r - 16 + rand 32;

But it doesn't give very good results.

Anyone with better idea for coloring ?