They could switch Nimble with Battle Forged. I adore Battle Forged so I’d hate to see it nerfed, but you’re right in that it’s kind of a no-brainer right now.
Steel Brow is great, but too weak for tier 3 perk. It’s just that it and Rotation are the only really powerful defence tier 2 perks, so it stands out.
Maybe make Nine Lives work once per turn? Powerful in certain situations, but you’re already near death and your armour is probably gone – it would fit the idea of a guy who won’t stay dead easily. Just needs a double tap.
Combine Hold Out and Fortified Mind into a single tier 2 perk. Move Anticipation to tier 1 and add another tier 2 perk. Being able to take both Anticipation and Nimble might be too useful for an offense oriented build, though, so it would require testing.
Return Favour synergises really well with Taunt. The defence tier 3 perks do feel less tempting than the tier 3 offense and utility perks. Going to need to play around with it a bit more to see how they stack up.