Dark Angels recieved several buffs to the units in their codex, in particular the Land Speeder Vengeance (extra HP, Plasma Storm Battery gaining +12″ range), the Nephilim Fighter (Black Sword Missiles becoming S7 AP3 and regaining Missile Lock), and the Dark Talon flyer (Stasis Bomb forcing Initiative tests, Rift Cannon increasing to S10 AP2).
Dark Angels also got point decreases for many units, new improved rules (e.g. Ravenwing rule allowing units to re-roll failed Jink saves, improved Grim Resolve allowing Overwatch at BS2, etc.), and access to Grav Weapons that they did not have in the past codex.
Finally, Dark Angels continue to have access to excellent units that no other Space Marine faction has, such as Deathwing Knights, Ravenwing Black Knights, Dark Shrouds, Sammael and his Jetbike, Ezekiel and his +1A aura, etc. Overall, I would rate the Sons of Lion as getting a SIGNIFICANT buff to their capabilities.
That said, Dark Angels lack some of the better toys that their Space Marine cousins have, including Thunderfire Cannons, Land Speeder Storms, Sternguard/Vanguard Veterans, and of course, the much feared Grav Cannon Centurions which dominate competitive games these days.
Lacking Grav Cannon Centurions, Dark Angels do have an alternative: the Grav Gun Command Squad with Sacred Standard. Now that Sacred Standards do not give out Counterattack, FNP, or Salvo2/4 Boltgun auras, they instead give re-rolls to Morale checks for all units within 12″ and give the squad carrying them Counterattack and Relentless. This is obviously a very large nerf, but they did go down in points and there is no limit to how many Sacred Standards you can take in army. This means that you can potentially spam Relentless Command Squads with maxed out Grav Guns.
Let’s compare the following two options, which have almost odentical points costs:
Option 1 – White Scars Grav Cannon Centurion Squad
-3 Centurions with Grav Cannons, Hurricane Bolters, Sgt Upgrade, Omniscope
-Fast Attack Drop Pod
-TOTAL POINTS: 295
Option 2 – Dark Angel Grav Gun Command Squad
-5 Command Squad Veterans with 5 Grav Guns and Relic Banner
-Dark Angel Librarian with Force Sword, Auspex, and Divination discipline
-TOTAL POINTS: 295
Now, both of these options allow you to drop in turn 1 and release 15 Grav shots at a target of your choice. Let’s compare the pros/cons of each:
— White Scar Centurions —
*Have Grav Amps, so better chance of wounding
*Have 24″ range, so better range for Grav weapons
*Have Hurricane Bolters, so more firepower and versatility against hordes
*Have T5 and 2+ armor, so much more durable
*Have S5 attacks if they are in combat and have Hit and Run (from WS Chapter Tactics) to jump out of combat and get back to shooting
*Can Split Fire, due to Omniscope
*Cannot fire overwatch or run (due to Slow and Purposeful)
*Do not have the ability to Twin-Link their shooting organically, so if they have a bad dice roll for rolling to Hit when they Drop Pod in, they are left hanging in the breeze
*They compete for very valuable Heavy Support slots (or require using a Demi-Company, if part of a Gladius Strike Force) in order to bring them in your army list.
*Ld 9, so pretty good for morale checks, but still vulnerable compared to the Fearless DA Command Squad
— Dark Angel Command Squad/DA Librarian —
*Have Librarian with Prescience, so more accurate and have insurance against bad to Hit rolls when the Drop Pod in turn 1
*Have 7 wounds total, so one more than “equivelant” Centurion squad
*Can Overwatch at BS2 due to Grim Resolve (or at full BS4, if part of a Lion’s Blade Strike Force), so very dangerous to assault them, unlike Centurions
*Can reduce enemy cover saves by -1 with Librarian’s Auspex, so able to deal more damage against enemy relying on cover saves to protect them
*Are Fearless, due to attached Librarian, so cannot be defeated with morale shenangians and are better at holding objectives
*Have 15 x S4 AP- and 4 x S4 AP3 Force Weapon attacks whenever they charge or ar charged, so more versatile in combat than Centurions.
*Have increased Deny the Witch ability, due to attached Librarian
*Have access to other Divination powers via Librarian, which can be quite useful (i.e Ignore Cover, 4++ save, overwatch at full BS4 even when not part of Lion’s Blade, etc.)
*Are an Elite choice, so do not compete for extra valuable Fast Attack or Heavy Support slots
*Range of Grav guns limited to 18″ (vice 24″ for Centurions)
*Only have T4 and 3+ armor saves, so much more fragile than Centurions
*Lack any form of shooting outside their Grav guns (i.e. so no Hurrican Bolters to deal with lightly armored foes)
*Do not have access to Chapter Tactics like Hit and Run (outside of their BS2 Overwatch)
*Cannot Split Fire like Centurions can (so potential for “overkill” shooting)
Overall, the Centurions are two MBs cheaper, have slightly better range/ firepower, and are definitely more survivable. That said, the Dark Angel Command Squad is slightly more mobile and versatile in close combat, has 100% better Overwatch abilities to protect itself against assaulting enemies, and has the versatility of an attached Librarian and his powers to make them useful all game long.
In summary, while a Drop Podding Grav Gun Command Squad with attached Librarian may not provide all the benefits that a Drop Podding Centurion Squad has, it is very close and has its own strengths to make up for it.
Given that Dark Angels can’t take Centurions, except as allies, I think this is a very viable alternative for their army when building competivie task forces for the Tabletop and complements the other elements of Ravenwing/Deathwing/Greenwing quite handily.