Your over thinking it. doesn't matter what country your friends with, its the player behind the country you want to friend.
Eg - Germany has joined 700 games won 0 has kdr of 0.33 they are not good pick to play with probably ditch you. now Poland has joined 158 games won 80 has KDR above 1.0 better pick why most likely to play the round with you
Think stats of player no the countrey