Work in progress
So far only marginal effort, if any, has been put into tuning these characters to appropriate power levels, either relative to one another, or on an absolute scale (based the game's starting level, which has not even begun to be determined).
In the heroic character lists, some characters are colored purple. This means the character is suitable for use as a player character "out of the box", although the character level will have to be adjusted to the party's starting level. You can just make up your own character too of course, or even create a good character who's similar to one of the evil warriors.