Thought of an idea that might spice up killer a bit more...

1)When you knock someone out you could take a small amount of rank off them, same scale as it would be for a ranked win but a fraction 1/2, 1/3 or 1/4

2)Kills being stored for say a month so you could get a 'revenge kill' and win double the rank back off the opponent

3)Number of kills in a row before losing could be stored as a stat

Good idea I like it

fairly obvious solution to this.......set the site back to how it was 4 years ago