Nah, keep the parry rate on camouflage. Evade rate is useless on bosses, normally. Evade could be good during magic pulls, but camo already gives -10% dmg taken anyway.

The only reason GNB's mit feels weak is because its invuln has an opportunity cost, and most people don't understand how regens are supposed to be used.

It's not talked about much, because it's far from ideal, but Brutal Shell being on the second hit of the standard combo actually lets GNB heal itself every other GCD if you really need to heal. Like it sucks, but I've won fights that way when the healer goes down. Pop Aurora on the DPS that either needs it or I suspect will not get hit to make it worthwhile, and then Keen > Brutal spam.

Also, Heart of Stone is better than Sheltron by a country mile, because you can apply it to other people, and it takes your Brutal Shell and puts it onto them as well. Like, sure, PLD has other skills in place that share the same resource as Sheltron, but one's on a long cooldown, and the other needs the PLD to have another CD up to really make ends meet.

I generally prefer other tanks for dungeons though, because GNB's AOE rotation is boring AF, and I prefer the gameplay of the other tanks. HoH has me burnt out on feeling great when doing the Continuation combo, but it's still cool AF. Though in some cases the shield from Brutal Shell is really really nice, especially when it prevents a damage based knockback by itself.