Your spec needs some work. Unless you're going for the Lichborne/heal spec ignore the Frost tree. Red sockets should be Parry/Stam; Blue should be Mastery/Stam and yellow Mastery. You're missing enchants and glyphs, but they're minor glyphs so no real big deal. I do reforge to hit so DS has less of a chance to miss, but others don't. I've tanked with 0 hit with no issue. Chest should be the Stam enchant. I've been playing my pally as my main these days, but the DK tanks fine. My spec is a bit off, but I'm too lazy to change it right now. The two points in Crimson Scourge can be moved, but other than that it's fine.
DS as much as possible, that will help a great deal.