From his perspective, not escaping would of been a death sentence, so I still say it was dominate or die. As for releasing them, he had to be certain that his powers held. Remember still all new. What he did to Gwen was largely uncontrolled, so she is what she is regardless. Releasing her would be a greater risk and reprogramming her is no improvement on what as already been done. It would still be him deciding who and what she is. And if he tried to reprogram her and send her back to the organisation, there would be the very significant risk that the changes would be recognised by them and then he would be in danger again.
With regards to the control/manipulation of the Aunt and others and true self, while what you say about inner desires is fair enough, that's not quite what I'm getting at. Chloe, in those few occasions where her true self does briefly re-assert itself isn't just expressing some inner desire that she would never act on. If released she would totally still act on them. Her true self is still there, it's just been over-ridden by the shell construct personality that the mc forced on her. And Veronica, Madison and the Aunt haven't been over-written either. In reality only very limited aspects of them are being controlled (Their reactions to the mc) and while I would agree that makes their decisions not their own and a theft of free will, the individuals haven't been destroyed. They are still there and everything done to them can be undone. The mc could remove the controls, without having to re-write anything in their personalities and they would go back to being themselves (although probably traumatised by the experience). Except for Gwen...