well in those cases i can understand, the Flash is a legacy, it's been passed down from generation to generation, so it's ok for them to have the same name, as for Green Lantern...technically there are thousands of them, and it's a police force, like the Jedi, so they can have the same names too..but i dont really know who the Crimson Dynamo is...
There have been 4 Flashes, 5 Green Lanterns and 12 Crimson Dynamos
I always wondered about the small town heroes, Say hero based in Wyoming and he's been active for years
I just tell myself, there is one Flash. One Green Lantern. One Hawkman. One Captain America. One Green arrow.
THAT is the problem. These others just get relgated to supporting roles, then get killed / damaged to make someone new look good.
Instead of using your "creative" skills to invent a new character to use an old identity, canabilize as much of that ideas as you can & use them for your EXISTING person.
when this happens it should be settle highlander style there could only be one after all
Luke Cage and Erik Jostens fought for the right to the name; 'Power Man" back in the 70's.
Erik (then a villain) had it first but Luke started using it.
They fought for it's use and Luke won.
Erik went on to become Goliath and now Atlas.
Ironically, Luke has discontinued his use of the name (though I wish he hadn't).