The old Bioware is dead, I'm afraid. Now it's just another studio that EA ruined. You could see a drop in the quality of their games as soon as they got purchased. Almost all, if not all the talent that made it what it was, left a long time ago.
Because there are a finite number of good writers in the world?
They could have the best writers in the world, but with EA's mismanagement they won't have great results. I suggest you familiarise yourself with EA's history of ruining studios they acquired. A lot of Bioware employees left because they were sick of unrealistic deadlines and other forms of pressure. They also fired the writers that created some of the best received characters and stories some time ago.
Can someone outline what an evil path looks like from a storytelling perspective?
I believe that are several types of evil characters:
1. Selfish, pragmatic, cunning and charismatic evil - often a leader type of character who manages to gather a following of like-minded individuals who bought into their vision of the world and want to support them. They can also be acting completely independently or as a duet with their romantic partner. They mostly care about their own needs and ambitions, they use underhanded methods to achieve their goals, form tactical alliances, don't care much for morality, and want to make their life/lives as best as possible.
2. Chaotic, unpredictable, murderous evil - someone who indulges in carnage, discord and disorder, they might not even have a specific goal in mind or change their goals frequently on a whim. They are impulsive, revel in madness, the more fireworks, blood and death the more enjoyable it is for them. They might consider killing as their artwork and will only briefly ally themselves with someone else if it's needed for their survival or they intend to backstab the other party.
3. Primal, destructive evil - the type of evil that does everything with one goal in mind - total annihilation and desolation. They might use the tactics of the other evil archetypes to further their ultimate goal but they won't cling to anything. They don't do it for their own enjoyment, they don't care about their own future, they only want the void to envelop everything and for life to cease to exist.
