So, I went through Deadlands with Isobel and Ember, switching out depending on the situation, and I got to thinking about what each companion does and doesn't like. This, in turn, got me thinking about possible future Companions with...alternative tastes.
1. The Wandering Daedra
ESO has already given us various Daedra that don't fit the 'norm'. Heck, Fargrave itself is full of them, but we have specific ones that we can interact with regularly. From a Skaafin who loves his Investigator Vale novels and just wants to be left to read in peace, to a Dark Seducer who comes to care for a mere Mortal and needs to rescue him from her sisters, and a Watcher who is tired of just watching and recording, and wants to just...be. And of course Lyranth, whose motivations are almost impossible to fathom.
So, how about a Daedra who wants that adventuring life? Dremora, Xyvlai, Skaafin, any humanoid would do. Eager to experience everything from assassination (which they enjoy anyway), to thievery, to big boss battles. Not fond of boring things like crafting, and hates Inns and Taverns...the smell of Mortals gets a little funky.

Best as a DPS (blades) or Healer (staff), but functional as a Tank (sword and board).
2. The Clanless Minotaur
Last of his Clan, rescued by the player, he swears a pledge of Honor to travel with you and fight by your side. His massive axe cleaves through the hardiest foe, and his roaring charge is enough to make the strongest foe start with surprise. He has no issue with theft, but fighting should be done with Honor...no assassinations. To run from a fight is to bring shame and dishonor, to fall in a fight even more so. Loves puppies...and maybe baked apples.
Best as a Tank (2H Axe) or DPS (Twin Axes), semi-functional as a Healer (Bow/Spells).
Just a couple of ideas that would spice things up a little, as well as giving us variants on likes/dislikes that we could throw into the mix.