Suggestion: you should use K/D ratio instead of K/D spread.
EDIT:
It's pretty impressive that you can track which weapons were used for kills. Would it be possible to track the number of shots fired/landed? An accuracy percentage (how many of your shots land) would be really cool. A stat which shows what percentage of your landed shots were headshots would be cool as well.
Player stat page ideas:
CTF win percentage (would have to put requirements in place for games to qualify, such as x number of minutes played in the game, or x% of the game played)
Team slayer win percentage (same as above)
Slayer win percentage
Average rank in slayer / team slayer / CTF
Caps per game average in CTF games
Kills per game average in CTF / in team slayer / in whatever
Assists per game average in " "
Deaths per game average in " "
You'd probably have to put requirements in place for a lot of those in order to weed out the times when people only play a small fraction of the game.
Also:
Caps per minute (or per hour or per 30 min, since caps/min would be a pretty tiny number)
Kills per minute
Assists per minute
Deaths per minute
Average life length
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