Bad idea for the following reasons;
1. DeathMatch often comes before refills, so the winner can be obvious when you bounty. If there are 2 pekoe in DeathMatch, one has full leather and the other full iron, I think that the latter will win, so it is just a cheap way I double your bounty.
2. This could be made corrupt where 3 people go into a game teaming, one dies, and bets all of his points on one of the 2 living souls, so the one without a bet on his head, lets the other win. Very simple, and very misleading for people that then look at the person that won the bet, some people care about points, and think that he is twice as good as reality.
3. This is also a bit easy, cause if you see Gravey4rd, for example, in full iron with no teams in the game, then you can bet all your points with no fear.
4. How stupid would it be I one guy kept on joining servers and betting on the obvious winner. He would soon have 10,000s of points.
5. You aren't allowed to gamble until you are 18 years of age.