A bit of luck with the dice and spoils will come into it, but it does for all maps. Nothing I can do about that.
Lets say a bonus region gives a +2 in the centre 4 squares, and this is the only small bonus on the board, I automatically assume that is what you will head for. There for, attacking the centre becomes predictable and boring. Right now, even in sunny games, you will have to think about how to place your 5 troops and where to attack without leaving to much of an opening. Like a game of chess, controlling the centre will make strategic sense, so to reward a player for doing that makes no sense.
The 32 centre squares are the only places to realistically put a bonus system in and as both players have to get across them for the other, you add to the element of luck, not take it away.
If let's say you have a bunch of territs out there that if taken together results in a bonus players have to figure out how to attack to take down as few neutrals as possible and get the bonus as fast as possible.
With the symmetrical board, it will be the same for both players or you end up with unbalanced bonuses and map that is easy to win on against new players.
but doesn't no bonuses mean dice luck matters more?
That is the strategy, luck of the dice will always be part of this game, even in game one, a player complained about the dice. Where you place your 5 and how you move will determine more of the outcome than luck of the dice. Adding in the bonuses takes away the skill and makes the dice even more important in the opening rounds.
DiM tried to take away the luck of the dice in city mogul, so that is a route that can be gone down. Larger figures mean bad dice will not result in a lost game.
So instead of the 1,3,5 ratio, I could easily put 4,12,20 or even higher. this is the ratio, I worked out to give the best results in making it an even game.
So you would look at figures like this.
1,3,5 (now)
4,12,20
16,48,80
32,152,320
the higher the number, the luck of the dice becomes less important.