There needs to be a medal for have been #1 with a weapon at least once in statistics, of course if you were before you will have to get it again; we can maybe call this the Weapon Mastery medal?
I have also been wanting a medal for Flamethrower or Ice Cannon hits
Also make a medal for killing like five people within twenty seconds each. Maybe Slayer medal, also a medal for killing 20 people without dieing... and a medal for having a bounty of 200 or more.
Eventually I hope for there to be so many medals you have to add an arrow to view the rest if someone has them all :P