AGE: 16 in canon, but aged up to 18 for the film
CANON POINT: Post-movie.
INCENTIVE: Mal has spent her whole life living on the same small island - the Isle of the Lost, where all villains in the Disney canon were banished to approximately 20 years ago following the election of King Beast as overall ruler of the United State of Auradon. The villains are kept from escaping the Isle by the use of the magical barrier, which seals them in. This also seals in everyone else, including their children. Mal hasn't known a life apart from it being on the Isle, and frankly, that's not a great life. Rotten food is commonly sent over from Auradon as provisions, as well as any other scraps or items that the Good People are done with as so have 'kindly' donated to the poor, lost souls of the Isle.
Her motive though? Well, let's see... Her Mother - Maleficent, Mistress of All Evil, curses you with all the powers of Hell itself? Well, she named Mal after herself, but refuses to call her anything but 'Mal' because her daughter hasn't proven herself 'evil enough'. Mal has spent her whole life becoming rotten to the core - at first only having an ally in Jay, son of Jafar, but through events in trying to retrive her mother's staff of power, gaining both Carolos de Vil and Evie, daughter of the Evil Queen to add to her little... group.
Then the new King - King Ben, son of Belle and the Beast - decided that four villain kids should be given the chance to live in Auradon. Cue Mal and her little group being chosen, and going along with a plan that Maleficent came up with. Don't come back without Fairy Godmother's wand. Long story short... this didn't exactly work out. Mal ended up dating Ben, and she didn't really feel all that comfortable with the idea of betraying one of the few people in life who had been willing to give her a chance to just be... herself. Her Mother ended up being turned into a lizard sort of by Mal's own power, so she's really not looking forward to the day that Maleficent gets out of that.
To sum it up? Mal is looking for a way to escape, if she was asked to explain it simply. With everything she went through, she knows that whatever comes next is going to be big and that she'll likely end up straight in the middle of it. Escaping that, even for a brief period of time? Well, that would be great. Being out of the way of her Mother's reach would be even better, because did she mention how she's really not looking forward to the day that her Mom works out how to turn back to herself? She doesn't just want to her her daughter, she wants to be her own person, and work out who she is and neither the Isle or Auradon will allow her that luxury or time to do so. So, yeah, if asked about why she was looking for a new place to be? The answer would be escape - from assumptions and from disappointed parents, just... escape and a place to herself. That would be pretty cool, thanks.
FIT: In Eudio, it would be an interesting clash between her natural personality and the want to at least try to be a better personal. Mal isn't shown to be all that comfortable with physical affection - though to be fair, she's received none in her life at all. Even with the dating of Ben, she seems to shy away from any real closeness, even when realising that her feelings are real and not just the result of the love potion she used to get him to like her. (It's a long story, and frankly it's part of that whole evil plan thing she'd like to forget.) However, around her friends it does seem to be a different story. Evie in particular seems to give Mal hugs without much in the way of her flinching away. Overall, it would be a good experience for her and allow for her own emotional development.
SAMPLES: An Ask Me Anything Thread with an avatar of Chaos
Annoying her 'Uncle', and trolling a Time Lord
ANYTHING ELSE? Though it's not really addressed in canon, technically speaking Mal is a member of the Fae - or at least half-Fae. She does have some inherent magic to her, but relies on spells and potions to be able to do anything of any real power. Unless we're talking about the green-glow eye battle with her Mother, in which case the feeling behind that can be very powerful indeed.