*Easily applicable to Halo 3*
Halo: Reach needs to have the 1-50 rank system implemented. As it currently stands the game is lackluster because there is nothing to strive for. The reason Bungie removed the 1-50 rank system was because of the amount of cheating that has occurred. This cheating included but was not limited to boosting, deranking, buying accounts, second accounts, and rank lock. Bungie could fix these problems and here are some possible solutions.
1) Have a decay system. If someone does not play for a certain period of time(possible a month?) in a specific playlist have their rank drop until they start playing. This would eliminate the buying or boosting of accounts because if the player is not good enough to have a 50 they would lose it. Either by playing and losing or if they decide not to play quickly becoming a rank 1 again.
2)Make the service record display the highest rank you currently have. This in conjunction with step 1 would stop people from obtaining a 50 and then not having to worry about winning or losing on it. For example if an account was a 5 star general but that account lost its 50 said account would become a brigadier general until it reobtained its 50. This would stop boosting because if people are cognizant of the fact that they are not as good as a 50 and know their rank will quickly decline they will stop buying/using booster accounts to help them increase rating. This in turn would stop deranking because if people stop buying/using booster accounts there will be no point in deranking.
3)Have peoples exp in the playlist reset if they lose either a lot of games in a row or after a certain period of time. This would accomplish 2 goals. Firstly it would stop derankers because without their mass exp in conjunction with their magnitude of losses they will not be able to boost other accounts effectively. Secondly by having the exp reset it would stop "rank lock" since the system would treat you almost like a new account.
In conclusion the 1-50 rank system is better then the current arena rank system. Although the 1-50 rank system has its problems if these ideas are implemented it would stop the current predicaments plaguing the rank system and eliminate abuse of said system therefore making it better.