As well as the default, other modders have contributed voice packs based on Wang Yuanji from Dynasty Warriors and the female Sith Inquisitor from Star Wars: The Old Republic. So far three voice packs are available, all based on women's voices.
Skyrim's protagonist has more than 7,000 lines of dialogue, so you can see why it's easier to get an AI to generate dialogue than having someone sit down and record it. You can select from a handful of voice packs, each created with ElevenLabs AI.