CHAOS WARFLEET
Ships not to touch:
Slaughter
Carnage
Murder
Hades
Repulsive (beyond what has already been FAQ'd)
Desolator
Infidel
Again, these are core ships and there's no need to mess with them at all.
Ships to have at:
Devastation - also a core ship, but just really quite strong compared to its IN analogue. Also strong compared to Chaos alternatives, with some usurpation of the Styx' role and devaluation of the Acheron's xeno-tech enhanced broadsides. Drop range to 45cm, demarcating this ship from both the Acheron and the Styx, improving internal balance and, in conjunction with the IN CV price decrease, greatly increasing external balance.
Idolator & Iconoclast - both these ships are too expensive. Like the Firestorm the Idolator suffers from a lack of role focus. The Iconoclast is a Cobra but swaps 2 torps for 2 WBs. Not a good trade. Note: even though I put the Infidel in the "don't touch" basket, it's not terribly strong. If it had 2 turrets it would certainly be worth its points, but the Cobra is a better ship for its cost. Still, it doesn't need any change.
Acheron - No change needed. This ship is certainly an odd duck but if the Dev comes down in range it certainly becomes more palatable. If I were to make one change to this ship it would be to increase the dorsal range to 60cm (+10 pts). This isn't in an attempt to usurp the role of the Hades, merely out of a desire to attain some sort of consistency. Hell, it could've dropped the broadside range to 45cm added some WBs or something and then increased the dorsal range to 60cm (ie, sort of like a lance variant Murder being upgraded to a Hades). Since it has gone for the the 60cm broadsides one would assume that the only reason to do this would be in addition to the dorsal lance range, rather than at its expense. Still, no change needed, just one of those niggling inconsistencies.
Styx - Drop cost to 260. It's still expensive at that price.
Vengeance series CGs - Vengeance and Executor are fine, Retaliator definitely needs some work. Increasing to 6AC seems a good start. Again, like their IN counterparts a refit table might be a nice addition, with the same caveat.
Despoiler - this model really needs to have its profile changed to match. I myself have done a conversion of one "closing" the prow bays and by simply replacing 1 WB hardpoint with a launch bay hardpoint this model matches the profile and it becomes fine (though perhaps a touch expensive). I have also done a conversion swapping the prow with a Repulsive prow and with the WB/launch bay swap this could represent the torp version of the current profile.
However, in the absence of such conversions it should have 4AC in the prow, instead of lances. Likewise, the broadside launch bays should be only 2 AC each, not 4 (there's only 1 bay on each side!) and the WBs should be upgraded to at least 10WB at 60cm. Strength 6 is unacceptable for 2 hardpoints. In this iteration I would drop the torp option, as there's no torp launchers on the model and the trade-off (lances) are no longer there.
Despoiler-based Power flagships - these should be adjusted accordingly.
Planet Killer - fine.
ABSF - a note giving rules for inclusion would be nice.