A completion highscores would be just like the game is now :P You can never complete the game as long as you have those highscores. You can always get a better rank/get passed by another player. In my opinion a 100% game would be 99 in all skills. All minigames played and won (Gotten to the chest at barrows, Won a castlewars game ect.) All music tracks found. All achievment diarys done. All quests done. That's pretty much a 100% game for me :P ©Tom®