I think you could drop the scourges with DLs. They're too expensive when you lose a gun with every wound, and you're paying for mobility you won't really want to use because of the -1 to hit with heavy weapons.
You can also drop the 10 man kabalite Squad. Kabalite warriors are good because they're cheap, and it's an easy way to get a blaster/venom on the table. They're a tax for a detachment and special weapon. It's not worth bringing 10 of them with no special weapon, and it's definitely not worth paying for 10 of them to just sit there. Put one of your units of 5 on an objective, one with a blaster in a venom, and one with the HQs in a raider. This also lets you drop a raider that you won't really miss.
Dissies are amazing at killing high save infantry like terminators, but terminators are so bad right now that you don't really need to be putting that much focus on it. Sure take one. One ravager with Dissies and 2 with DLs is good, but give your Razorwings Dark Lances. It's just more consistent and saves you points PLUS is better at killing things that would really wreck your day like superheavies/tanks.
Look how many points you save, and decide how to spend them.
Consider stock scourges with shard carbines. They're not too expensive, they're super mobile and can bully objectives really well with their assault 3 poison. 5 man squad for 70 points is really solid, especially when most of the rest of your list is built around Dark Lances.
If you're feeling brave think about bringing another RWJF, and grab the command point for having the flyer detachment. That does have you sitting there with 510/1750 points in the air though making it possible to table you by killing just 1240 points. But hey, to do that they need to survive your onslaught, right? Plus that'd involve them letting your flyers just walk all over them while they chase your other units around the table.
I'm not sure why you're bringing the Haemy when you could replace him with another archon and save some points. Sure the haemy might be able to kill more in melee but your whole list is built around shooting, and you don't have any haemonculus coven units who's toughness you could buff.
Warriors with Blasters in Venoms with Splinter Cannons give you a great unit for kiting people around from 18". Stock 5 man warrior units in Twin splinter rifle Venoms give you a 115 point unit with 20 poison shots a turn from 12" with -1 to hit and an invuln save. Plus the 35 point unit of warriors is cheap enough that you could drop them on an objective and move on to keep fighting with the Venom without feeling like you have a pile of points just sitting there. These are safer picks than scourges because they're a lot harder to shoot off the table, but they're also more expensive so you can't have quite as many of them. Think about adding PGLs to units in vehicles. If you know you're going to be putting a lot of firepower into 1 unit, make sure the PGL is within range as well just for the extra chance to kill another model in the morale phase.
These are all of the things I have for you to think about.
Cheers