Okay, i keep seeing Kestas mention saturation will help the map, and it won't on its own, a saturation will increase the colour definition, but that alone won't solve the problem.
a good technique when colourising is to set the saturation for all colours *individually* to +20, and then to add a darker filter for -35/40, people think the darkening filter will actually counter act the colouring, but it won't simply because their completely different.
You want all of the colours to have the same shading, i think even basic graphic allowances can offer that, if all of your colours were simular in shade, then they'd blend perfectly, as for the arrows, maybe change the colour of the support, since it's yellow, it might be weird seeing yellow on dark yellow.
I leave the colours to you, but if you make the arrows maybe smaller, visible, but not so IN YOUR FACE as the current ones, and then make them stand out a little more, it should work...the picture in my head works anyway, and thats how i'd do it.
Also about room, you could revamp the map, i know its based on the diplomacy game, but places like moscow and saint peteresburg really don't need to be so big, when other countries are pretty tight. Still thats for an entirely different thing.
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Convoy Bug
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