A grading system for each gamemode/sector of modes would be cool (a sector being either rvb/meetup, duels, uhc gamemodes, ffa, etc.) What a grading system would do is count up all of your wins from a mode and give you a grade. To make it not sweaty, losses wont effect a grade.
How it could work (in duels for example):
Level 1: 100 wins Level 2: 250 wins Level 3: 500 wins Level 4 1000 wins
How it would look:
It could be graded by silver-gold-diamond... knight-elder-legend... or something else