Well, in D:OS, it seems that spells are a kind of skill. I think there's nothing wrong with that. As I've played previous Divinity games, I have to say I like this new approach. In the old system, you need mana to cast spells which is how you'd differentiate them from a skill. While that's all great, it makes it harder in a classless based system. I think the action point approach works out well.