It is one thing to convert distances from miles to kilometers. I do it every time I ride in a country that measures distance in kilometers. But, I think in miles. I have no idea how many feet are in a kilometer, but I know that the conversion from miles to kilometers is to multiply by 1.6.

Suggesting that "Miles are becoming almost as obscure as furlongs" is a bit over the top, I'm afraid. No one in the US uses kilometers. We also use English here. Should I offer a French or Spanish version for all those young people who see English as "obscure," as well? And, what about using dollars as a currency? Shouldn't I also allow people to convert them to their own monetary units?

Whatever units I pick, there will be someone who finds them inconvenient.

If I did the conversions as you suggest, the numbers would not match between the 2 versions. For instance, 2 points a mile becomes 1.24 points per kilometer. If I do everything in kilometers, then 2 points per kilometer becomes 3.2 points per mile. I could round-off these numbers, but than the two versions of the game wouldn't be equal. What's more, how careful do I need to be in my conversions? Do I need to estimate it to one decimal place? Two? It will quickly get far more complicated than it needs to be.

As always, I value your opinion, but I don't see how to implement this conversion in a simple way.