Where to go from here?

I collect basically everything Chaos for 40k. I have Knights that I've picked up over time and built for Rule of Cool, and outside the Abominamt for the recent Nightmare Hunt detachment for CSM I've not put any of them on the table.

I have:

1x Knight Abominant

1x Knight Desecrator (built with a claw)

2x Huntsman

2x Karnivores

What can I do with this and where should I take this to make it into a viable army on their own? Do I need another big guy?

I have loads of cultists from my CSM forces so is Iconoclast Fiefdom worth running?

What's the best way to go from here?