We can approach this subject two different ways.
First, we can look at it from a roleplay perspective. The perfect example as a good red would be KSS, who went red not from "pking" or "being evil," but went red out of defense of the innocent, justice, honor.....Another example of "good reds" would be when we (me, Gib'dat, and others) roleplayed samurai defending the Tokuno Islands from invasion. We might have killed anyone who invaded and refused to leave, but we were still good reds because it was being done for defense of our homeland, and we were very honorable about it.
"Bad reds" from a roleplay perspective would be what BORG is now. We are the "evil" roleplayers. We are a race of cyborgs on a quest for perfection, assimilating other races into the collective without mercy.
The other way to look at this doesn't consider roleplay.
The "good reds" are those with honor, not necessarily honor having anything to do with roleplay. These reds are good guys. They're not going to rk you without reason, dry loot you, kill your mount, [censored] talk, grief, etc....They're still PKs. But they aren't ass PKs.
The "bad" reds would be the ass reds. They're the griefers/jerks. They're the ones who will dry loot you, rk you, kill your mount, [censored] talk, etc.....
"Good reds" from a RP perspective are the reds with a good purpose, such as justice, or defending their homeland from invasion. The "bad reds" from a RP perspective are those with an evil purpose, such as BORG or vampires. Though imo BORG can also be seen as good in a way since after all we are just trying to improve your quality of life
Not considering RP, the "good reds" would be the honorable reds. And the "bad reds" would be the jerks.
I suppose BORG would be good bad reds....since we're honorable reds with evil rp

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I hope that helps

. Confusing ain't it? Hehe.