Well, first of all, I think you're taking level a bit too seriously if your primary goal is to level up.
Second, the guy at the top of the leaderboard is proven to be gaming the system.
Third, high level players with a lot of games under their belt still rise and drop levels consistently, so I doubt that it would be significantly easier to reach a higher level if you start a new account. If you play like a level 32 player, then you will plateau at level 32 no matter how many new accounts you start.