So you get a bunch of FREE spells and yet you guys still look for ways to justify getting them at the lowest spell level?
I would assume since Hexcrafter is an archtype of Magus, you would use the spell level of the wizard/sorcerer(since you know, everything else is based of this). Why would you use the cleric list if you can pick the same spell from the wizard/sorcerer list? That's just cheese.
One can assume the free curse spells were meant to come only from the wizard/sorcerer list. But the text isn't clear, so I can understand taking the lowest spell level version in those cases.