Werewolves
Fairies
Witches
Genie
Zombies
Robots
Mermaids
Imaginary Friend
Super Heroes
Something New (optional)
Good question. I love Supernaturals and fantasy gameplay, so I think about this a lot.
1. Witches
2. Fairies
3. Mermaids
4. Superheroes (we've never had these before, right? First I've ever heard of them other than as in a career in Sims 2... but I'm SUPER onboard. No pun intended.)
5. Genies
6. Werewolves
7. Plant Sims (proper ones, like someone else said.)
8. Zombies
9. Imaginary Friends
10. Robots
For my 'something new', Hmmm... I like the idea of elves since they kindasortanotreally had them in Dragon Valley but they were literally just sims with rainbow skin tones and pointy ears. But to me elves are basically just fairies without the wings. In some fantasy (they touched on this in Sims Medieval with one townie) dragons have both a human form and a dragon form that they can shift between, so that would be kind of fun. (I just really want a medievalish, fantasyish, Dragon Valleyish pack... please oh please oh please)