To start off, it's clear you know what you are doing, since you are already generally in the top 10% of parses or higher. So most of my suggestions will be small areas where you can improve on what you are already doing, rather than stuff you are missing.
Shield Block uptime - You are ~70% on most fights, including Lightblind Vanguard, you should be 90%+. Defensive value aside, your Shield Slam damage is increased by 40% with Shield Block, so this is very important to focus on.
Defensive Stance - you're 100% in defensive stance for all your kills, but I don't see your health generally being threatened. Try to go battle stance more often when nothing happens and you can do damage - two examples are Saladbar in his burn phase and Vorasius for the two full minutes where you are not tanking him.
Talents - In the Prot tree I see you are running Battle-Scarred Veteran and Massacre. I would suggest placing these points into Thunderlord and Tough as Nails for most fights as you don't ever really drop low enough to actually proc BSV and execute, while useful, is not as powerful as it was, so more casts of demo shout and passive block dmg will result in more dmg, especially against multiple targets.
In the Warrior general tree I see you are not picking Crackling Thunder. While this is very minor it does help hitting adds that are spread out, so this could allow you to get aggro (or pad) easier on some fights. I would also suggest you swap Fearless or Piercing Howl for Wrecking Throw. At least three fights I can think of include absorb shield mechanics which WT is amazing against, and if you are forced to run out of melee it does more damage than a Heroic Throw anyway.
Shield Charge - use it more often. Some fights you only cast it three times. It increases SB uptime and it does double damage with tier, so use it on cd, and if you are not running Thunderlord always with Demo Shout.