[member="Drios Rapux"]
All of these names sound just fine. If I had to point at one that sounds better, I would say Ajanus. It's not a name I've heard before, yet it rolls of the tongue nicely. Ardyti seems more like the name of a pawn than a player. It would do for a henchman, but never a villain in truth.
Taking on the mantle of Darth and a name of the Sith, is a very important matter. The name one chooses is the name that is etched into one's legacy. Legacy is at the heart of Sith Philosophy (See Darth Bane's Rule of Two; on apprentices). Therefore, be mindful of the name you pick, because it is a name for eternity.
Now, my general idea when picking a name is to look at 1: What my character does, 2: How she does it, and 3: Why she does it. The what and how is simple enough. It lends to your character's approach to problems, be they a schemer and manipulator, direct warrior, or a stealthy assassin. Generally, what is the theme of your character? Once you have an idea, you look at their motivations; the why. The why is very important. Motivations makes a character good, abilities are just the physical manifestation of said motivations.
When you have these things in mind, you may find symbolism and mythical figures that befit these themes. Don't jump on the first you find, keep looking and you'll find something great.
Now, I would like to quickly mention the "when" of a Darth-title. I for one, would never allow an Acolyte to bear such a title, because they have not proven themselves to be strong enough, yet. They are hopefuls, not darths. A knight may claim their name, and a Sith Lord, I would expect to enforce it.
