Time and time again, players of Death Eaters have been having this problem. They are told certain skills are needed for the Dark faction, so they create a character who fulfills those needs. As they RP, they find themselves RPing in impromptu social/character-development scenes less and less. Then they don't bother, and only log on for pre-planned TP events. And when they're really bored to tears, they kill the character.

This cycle can end here.

Take this into consideration: Why are the good guys more proactive than the bad guys? Terribly cliche, but it all comes down to one thing: love. Love for family, love for friends. See the Nosfertums, the Drakes. They will do anything to protect their loved ones, and the players see clear motivation in bringing them out to play. The Order is one big happy family of love. It's their strength, it's also sometimes their flaw, but it's what makes the characters human, real, and unbelievably connected to the player.

Love is what's missing from the Death Eaters. But, you say, Death Eaters can't love! What is there to love about Voldemort? Not much, I agree. And the Pureblood mentality, much like anti-Semitism and racism, is a hard one to truly understand and roleplay. More often than not, players make this mentality flat and one-dimensional. But is anyone willing to fight any abstract causes? No, not even when the cause is to stop the spread of Dark Wizardry. What makes a cause a truly motivational factor, something worth dying for, is the tangible. The death of a cousin. The betrayal of a best friend. The sight of a Dark Mark hovering over your home.

And so it is for Death Eaters. Love can be a strength, but it also causes people to do silly, nonsensical, downright stupid things. Here you are, your family was once renowned, your grandfather told you tales of the good old days, and Wizardkind and its traditions are dwindling. The Ministry constantly bugs your father about searching your manor, your mother is struggling to make ends meet, and then... Your brother tells you about Lord Voldemort. Suddenly, the tides seem to be turning. There's a shred of hope of making your family proud. When your brother dies in an Auror raid, you see joining LV as the only way to avenge him. Anyone who's ever grown up in a family with strong traditional values will understand that these ties are not easy to sever.

Then fighting for Lord Voldemort does not seem as much of a lost cause as it is meaningful character development. Two key things that you should keep in mind when making a Death Eater:
1. Is the Death Eater, first and foremost, a character? Having a needed skill for the faction is one thing. Basing your character on that skill is a formula for boredom. Aurors aren't played because they're good combatants or investigators-- neither should DEs. Start with a human, a CHARACTER concept, and then decide how being a Death Eater fits into it.
2. Does your Death Eater have strong motivations or ties? The easiest way to go about this is to make him have a family. Wanting Purebloods to win is not enough. Being sadistic is not enough. Love is the strongest motivator out there, so be sure there is something other than Voldemort that your character is willing to die for.

Examples of Death Eaters who have made this work:
-Zellah Redwater comes to mind. She had something to protect, and she stopped at nothing to protect it.
-See the books. The Malfoys. The Blacks. The Lestranges. No doubt they all loved one another, and they had great dynamic. See how willing Narcissa was to ask Snape for help even though it meant Voldemort could kill her. See how willing Draco was to join LV to gain back his father's favor, even though he was just a scared 16 year old.
-Charlotte doesn't even believe in LV's cause. She was pressed into the ranks. Now she must battle with her conscience as she puts Auror's lives in danger while also doing her job to the best of her ability to keep her cousin safe.

There are now DE families on the grid and openings to take family members. I highly suggest, if you decide to get rid of your current DE alt or make a new one, to join one or at least make a character with connections to those families. Please don't let DE alts just idle out. Arrange a capture with some Aurors or let them die in battle.