Since White Scar armies with Kor’sarro Khan as their Warlord still maintain the ability to Scout all Bike units and all units embarked on Rhinos/Razorbacks, that opens up some signfiicant possibilities for a first turn, Graviton weapon “Alpha Strike:”
1 – Take the Gladius Strike Force with a Full Battle Company as follows —
a) Khan on Bike and Chaplain
b) Command Squad with Bikes and 4 Grav Guns and Apothecary
c) 6 Tac Squads with Free Rhinos and Grav Cannon
d) 2 Bike Squads with Dual Grav Guns
e) 2 Devastator Squads with Free Rhinos and 2 Grav Cannons each
2 – So, altogether, that gives you 3 Bike squads with 24 Graviton shots a turn, plus Scout to get within range turn 1. You also have 6 Tactical Squads that can Scout in their Rhinos and then let loose with 48 Graviton shots total, as well as 2 Devastator squads that can Scout in their Rhinos and put out 20 Graviton shots a turn. Total, that is 92 Graviton shots from Scouting units turn 1!
3 – Since you have so much anti-vehicle/heavy anti-infantry shooting, about the only thing missing is anti-horde capability and anti-flyer capability. To deal with this, you can supplement this force with a Storm Wing formation (i.e. Stormraven and 2 Stormtalons), kitted out with Typhoon Missile Launchers and TLed Assault Cannons (Stormtalons) and TLed Lascanon/TLed Multimelta (Stormraven). This should provide a very versatile options for dealing with enemy armor, massed infantry, and flyers/FMCs, providing the ground elements with all the support they require.