One for Sorrow

Yes, I mean, I think the differences between the characters are all really interesting. We don't know much about Regulus but even he has the potential for a unique story for how he got where he got. It's just very hard to explain away joining the DEs for any good reason. Although sometimes it probably comes out of someone explaining stuff away all along, so joining the DEs is just one more thing the character was forced to do or didn't mean. It's not that they can't join the DEs for reasons that aren't all completely evil--wanting to prove onesself a man, avenge one's father, get back at people who were evil to you. You can include those things without avoiding the real bad thing the character himself is doing.