Do you have the Index?
Have you seen any of the new codices?
If not, I can send the info -
PM me.
Use what you have.
The
DG are gonna stay
DG.
You could trade them.
Or, use them as a separate detachment
and use until yo get your purestrain EmpChild army rollin.
Are those regular space marine bikes?
Put the extra spiky bits on the bikes,
add moar skullz,
maybe use green-stuff to sculpt the odd nipple clamp,
maybe add the odd sex-slave in chains,
and stay general purpose,
get your paint job down,
...
Noise marines. You need noise marines,
so maybe pick up a few of the sonic blaster packs,
and
you need these:
https://www.forgeworld.co.uk/en-ES/Emperor-s-Children-Legion-Kakophoni
Perhaps also use these:
https://www.forgeworld.co.uk/en-WW/Telerac-Pattern-Volkite-Culverins-Set
And I like this model pretty well:
https://www.games-workshop.com/en-US/Chaos-Space-Marines-Lucius-the-Eternal
Maybe add a vindicator or similar, nothin like Slaaneshi vehicles spurting mortal goo all over the table.
Oh yeah, add some warp talons. Cool models.
Maybe you can trade off or sell those Primaris marines for something on the list.