I would like to suggest being able to view other players stats.
On the leaderboard, add an icon next to name to view stats.
When viewing players (in a game) a box giving their stats.
Stats could go into a lot of detail but I suggest in addition to info already displayed......
Preferred # opponents
All time wins
2nd place, 3rd place etc
All time losses (last place finish)
Current rank (as in X out of X players
Highest rank (x out of x players)