It would make much more sense. 90% of the PB2 player base (this was always the case) is running around with Advanced Marine ranks which is kinda stupid considering there's also a Marine rank right below it.
Imagine that the U.S. army had more Corporals than Privates, because that's the case in this game. So, the solution would be ranking players based on their performance compared to the other players. There's it:
Advanced Pacifist: Worst 100 players, most of them would belong there by dying on purpose
Pacifist: Worst 0.5% of the playerbase. Still an achievement
Newbie: New players with less than 30 kills or deaths.
Marine: The lowest 44.5% right after the Pacifists (99.5%-55%). Average players.
Advanced Marine: 25% of the players right between Professionals and Marines (55%-30%). Strong average.
Professional: 12.5% of the players between Elimination Masters and Advanced Marines (30%-17.5%). Above average.
Elimination Master: 7.5% of the players between Race Rescuers and Professionals (12.5%-5%). Good players would belong here.
Race Rescuer: 3% of the players between players ranked PROmoted and Elimination Masters (5%-2%). Very good players.
PROmoted: 2.1% of the players right after Race Rescuers (3%-0.9%). Excellent players.
Elite Commander (or some random title): 0.899% of all players (0.9%-0.001%). Some of the best players.
Honourable Warrior of Plazma Burst 2.5: Players in the top 100 who aren't in the best 20.
Legendary Warrior of Plazma Burst 2.5: Top 20 with the exception of the Silver, Gold and Diamond Legends
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Of course, there might be more ranks in PB2.5 but this approach is far more logical than using only a player's kda.
These ranks would be based on Player Points, of course.