The goal of V6 is to fix the issues of V2 (HDR effect), V4 (circular compositions and too low realism), V5 (low contrast, too high sharpness, bad eyes).

Recommended settings:

Start with Euler + Beta. Optimal contrast and quality.
Euler A + any scheduler. Extra smooth, low contrast, low sharpness, clean textures.
Dpmpp 2M. Extra contrast with bold lines.
With Euler and Euler A you can use CFG higher than 7. CFG 5..7 usually gives more realism. Overburning starts at CFG 10-11.
Portrait resolution I usually set is 1024x1280 or 960x1216. You can start with 832x1216 and increase until you get duplications (usually at 1440 by longest side).
For the 1st pass I usually go with Steps 20-30. For HiRes Fix or Ultimate SD Upscale Steps 8 is enough to fix most of the issues (with Denoise 0.29..0.39).
For prompt start with Booru style tags from sites like Denbooru or aibooru.
Natural language also should work. I add natural language prompt after Booru tags.
Some PONY embeddings work as usual with this version. Some of them might give bad results. Didn't test many of them.
SDXL / Pony / Illustrious LORAs should work (style related LORAs which don't depend on prompting).
Illustrious characters from anime world most likely won't work. Special training needed and it was out of scope of this release. Sorry.
This version love creative, horror, cyberpunk themes. It also renders good scenes with greenery, waters and natural light.
Male and female characters should work. Biased toward females. No specific training on gay themes.

CinEro Illustrious V6 RC1 - RC1