The coins are the same randomness of drops. Nothing is actually "earned" in this game with the exception of the Vex Mythoclast. Strange coins are easy to come by, and they hand out 9 a week really easily through the weekly heroic strike. I would like to see an increase of the cost of the items Xur sells. I think everything should be doubled at the least. It would make people value exotics more and really make them decide which one is worth the coins.