I would keep their powers/abilities, but give them power rings and make them like the "new guardians".

1. Red - Flash - anger increases speed or speed helps defuse his built up rage
2. Orange - Aquaman - greedy for glory and hordes things in an under water cave, or Atlantis, his material greed somewhat tempered by being a king, but his moral put more emphasis on heroic glory and jealousy of others taking the credit
3. Yellow - Batman
4. Green - Hal Jordan
5. Blue - Superman - allow him to make physical constructs like saint walker (without a green lantern around)
6. Sapphire - Wonder Women
7. Indigo - Cyborg - his staff could be energy based cybernetic extension

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1. Red - Cyborg - cybernetics help control his rage
2. Orange - Flash - he is greedy for glory and uses speed to take out as much bad guys as possible, but also steals, their toys...for safe keeping
3. Yellow - Batman
4. Green - Hal Jordan
5. Blue - Superman
6. Sapphire - Wonder Women
7. Indigo - Aquaman - has a trident instead of a staff

-------------------Swap Jordan with Martian Manhunter----------------------

1. Red - Cyborg or Flash
2. Orange - Flash or Aquaman
3. Yellow - Batman
4. Green - Superman or Martian Manhunter - change the nature of the of the blue-Green relationship
5. Blue - Martian Manhunter or Superman - change the nature of the of the blue-Green relationship
6. Sapphire - Wonder Women
7. Indigo - Aquaman or Cyborg

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Another option would be to have MMH as indigo as his shape shifting would be cool with their ability to channel different emotions