Under the Qun, they'd have purpose -- they'd have a reason to get out of bed in the morning and be part of society. Under Tevinter, with Dorian's idea, they'd have that work, that purpose, and get paid to do it.
You keep talking about freedom, but you're forgetting that some of these people might not want the freedom you're trying to sell them. Teaching them how to be free doesn't mean shit when they're busy trying not to starve to death.