Thawing should be absolute #1 priority; killing should be second.
Rather than go out looking for the enemy to kill, use the radar to go out looking for teammates to thaw and if you encounter an enemy en-route then go into kill mode. This way you become much more effective as a Freon player.
Too often the sole surviving player on a team will play out the round like TAM, trying to engage multiple enemies, rather than looking for team-mates to thaw. With the odds stacked heavily against them, more often than not they'll lose the round for their team.
With two evenly-balanced teams, The team that thaws more inevitably wins the games. A lot of people will call 'teams' on an unbalanced game where the team average PPRs are similar or even higher on the losing team. The differece is not in skill, it's the number of thaws made by the team in front.
So check the average PPR first and if they are similar or stacked in your team's favour, don't call teams, encourage your own team to thaw more.