Thought I'd follow up and comment on the bikes, I think the bikes are fine I guess but I'm not sure they will be taken that much of the time. See the biggest problem is the slot they occupy vs cost. The Scout bikers are a fast and compete directly with the raven bikes and while they aren't taken that much they can actually output some stupid high volumes of fire. And their cheap enough to have value in small point games where the capacity to take more of them may outweigh fewer normal raven bikers, ravenwing bikers have their synergy with ravenwing keyword as well as probably being cheaper base along with their capacity to take special weapons in their roster. I think these will be the primary contender with the primaris outrider.
Outriders are not better then black knights, black knights occupy they spot in the army that they simply have no capacity to replace. Black knights hit harder thanks to Corvus hammers, they roll faster cause of ravenwing keyword synergy, and the plasma talon is the pinnacle of consistency. It's a weapon that can output some of the wildestly static numbers In the army and that can really go a long way. Nevermind the formation in vigilus that requires the use of them which may have applications going forward with the cp
On top of that ravenwing black knight kits build into the 3 characters and the apothecary a might as well be glued to your army list because of how useful they are. And the ancient and champion have uses too that can't be discounted.
I think the biggest thing we will need to sit and wait on is the hellburners as I'm calling the melta primaris. They could be good, especially if we finally see a primaris drop pod or even just in an impulsor running across the table to drown an enemy high value target in melta blasts.
The executioner also could be really good, at present the dark angels have no good character duelists really, the ravenwing champion and Ezekiel are the closest things and they aren't even really that good (both really are only good at killing secondary hq's and characters like mekboys, other company champions, aspiring champions etc ). If he is good enough, we may see an interrogator executioner and that could be really really nasty, like better then chaplain immodiu... I mean asmodai. And that says much.