I admit I don't have the supernatural ep for reasons but I would love it if the witches had their own history and community like in Harry Potter
They could also have toy brooms for kids(toddlers?) that levitate a few inches off the ground and the kids have to be taught how to ride a broom (sorta like how you teach to drive a car)
Remember that cave with the creepy eyes? Maybe it is an illusion for muggles and they could go through it to their own sim Diagon Alley
Oh and butterbeer...and firewhiskey...maybe the ability to make candies that have magical effects
Maybe the witch kids can have their own ways of pranking the town/school
Maybe the witch adults can use magic to cook and clean things without needing to supervise it (however that could take practice and if too low in experience can result in a fire)
From what I've seen in the Youtube videos, better routing for the brooms (not sure if it's possible but maybe they can really go by air instead of just following the road)
Others are asking for sims 2 car animations, how about being able to actually see them get on the broom, and maybe be able to make a flying car...
And sense there were so many gnomes, have one magical witch gnome again
Instead of needing it from store, have the cauldron and voodoo doll available via EP
(sorry, most of my witch/wizard experience is from Harry Potter :P)