From a villains standpoint what Enter did was very clever. You want to kill me... kill Red Buster first! Having Hiromu as his back-up was his trump card indeed. Though Escape rebooting got tiring after a while what with her keeping introducing herself over and over.

Yeah; it really is a great trump card that he played there.

Though if he becomes a perfect human, wouldn't he then be killable?

Actually that's a great thought. I'd say in the end that the last data he'll need is Hiromus' willingness for self sacrifice. Once he has that he'll be a 'perfect' human. Once he's human he'll be able to die.

Honestly, just watch the first 8 episodes, skip to Jin's introduction, then right to 33-35, and then jump to 42 and continue from there. Everything else in the series is pretty lackluster and pointless.