This is an issue that I would recommend that you wait until you get the game to decide if you like things like the blue used for lakes and rivers. I started beta testing before the map tiles that are currently used were in the game. When they were first introduced my initially reaction was "kinda a step down from FPG". However, as I have fought numerous battles over them my comment is "hugh improvement over FPG". There are not as "pretty" as FPG, but they are more functional. When I play, I don't even think about the artistic look of the maps anymore. I am usually thinking of the tactical value of the locations on the map. You don't have to quess like you did in FPG. Their overall value is usually fairly obvious.
In some of the screen shots posted I didn't like the color of the blue either. That was because of the quality of the screen shot. The blue in the game does not look like some of these screen shots. Some of the screen shots do not do the maps (and the blue rivers) justice.
Btw, if you don't like the blue. you can load the maps in a map editor and using color replacer replace the blue with whatever color you like. I just tried it and it took me just a couple of minutes to change an entire map. In fact it took me a lot longer to write this post than to change the color of the rivers and lakes on the map.
