Play A Friend
Make a private invite to have a match with a friend. This way, the two of you can work together to level up a character in an elimination match. There is no penalty for allowing one player to get all the points, so you might as well make life easy. Set up a private match, allow only your friend to join and let one of you continually win. This might sound like cheating, but it is a surefire way to get those points.
Elimination Versus Team Elimination
Elimination is a much more effective match setting for leveling up your character. Though team battles mean you have a chance at gaining points from your teammates, it also means there is a higher risk. Unless you are playing with close friends, it is better not to gamble your points with other players. Keep to yourself in an elimination match, or even play on an unofficial team in elimination matches so you won't be punished for others' mistakes.
Data Posts
If you are playing a ranked match with a friend, data posts provide an opportunity for both players to gain levels. Simply find a data post in the level, and spend the match "stealing" the data post from each other. There is no point loss for losing a data post to another player, so both players gain many points per match. This way, no one loses precious points for dying.
Vital Suits
Players earn multiplier bonuses for defeating enemy players who are using vital suits. Turrets only give players a 1.2 multiplier, but speeders multiply your score by two, and other suits can go up to three. This is a quick way of earning a high score in a match. Find a suit as quickly as you can, but do not use it. Instead, wait for another player to grab the suit, and then take him by surprise. If you develop strong tactics for getting the jump on players in vital suits, your score will skyrocket.