Honestly I think they're going for a glass canon vibe. I don't think Arc is a class about tanking damage, it's giving damage in bursts and darting away. But I understand how that's not matching the 'go forward' tagline of Arc. Perhaps if Amplified made you immune to any slowing effects like Wizards dark cloud, and Jolt deals heavier stun so you could strike and move. That would help you survive without being more tank-y than the subclass needs to be.