Honestly, I hate to say it, but WE are pretty much figured out competitively. There are people still trying without it, but I believe 2 forgefiends are the only thing keeping us in a large number of matches. DG is absolutely one of those matches. For your list, the eightbound could be split up. The 2nd berserker/MoE unit is probably not worth it. Could be replaced with a Lord on Jugg for 1 of the eightbound units, and the 2nd fiend you would need. This is all just pushing you back to the pretty basic Berserker Warband being run. Sad, but this isnt an army with flexible options. You're excited for that Ultramarine codex, though, right? RIGHT?

Edit: If you want the breakdown, I haven't been playing since dataslate, but I think winning competitive lists are bringing:

• Daemon Prince on foot
• Kharn + 10 berserkers in a Rhino
• Slaughterbound + 3 exalted
• Lord on Jugg (with glaive) + 3 eightbound
  • this one might not be in every list, but its a great unit that trades up.
• 2 units of Chaos Spawn
• 2 Forgefiends
• 1 Helbrute
• a Jakhal unit for your backline

That leaves you 255 points to flex. 235 if you put Helm of Brazen Ire on the DP. I'd probably just take another Chaos Spawn, another Helbrute, put Favoured on the Slaughterbound, Helm on DP and call it a day. Like I said... mostly figured out.