First time posting here, and first time, in a very very long time, finishing a personal project ( thanks covid ).
It’s also my first blender project since I stopped using it 13 years ago, I had my eyes on 2.8 since the alpha, but too busy at work and life to actually try it on a real project.
I worked in VFX and CG for over 10 years, using 3ds max / maya / katana / nuke / Mental ray / Vray / arnold / renderman .
For this project I used : Blender / Cycles / Substance / Fusion
So basicly, the chalenge was to use free, or affordable, softwares for the entire project ; meaning, softwares that I never used or did not touch for more than 10 years, and that I never used in high end productions.
If anyone is interested in my opinion, blender can replace commercial softwares for most tasks, but cycles will fail to meet the standards for high end rendering pipeline. It’s totally ok for a free render engine, but I think we need to acknowledge that the gap is huge compare to commercial render engines like Vray or Arnold ( even if we are comparing it to previous versions )
If you want a more feature rich free render engine in blender, I would go with radeon pro render, however, you will miss the seamless integration of cycles in blender.
Also, no dome light and no light linking in blender, no matter the render engine.
I think I pushed cycles to the limit with this project, and it’s a simple scene compare to what I am used to work with.
10hr at 3840x2160 withRyzen 3600 using intel denoiser ( I don’t own a nvidia GPU, so I went CPU ).
With same CPU in Arnold, I could not only get this render in half the time, but also get a better quality.
I spent 2 days trying to understand how the branched pathtracing and adaptative sampling in cycles work, but I could not get the same results I am used to in other render engines.
I am not saying this to make blender look bad, I actually want to be able to use blender more often, and I want to know if anyone had similar experience coming from other render engines or if I am just an old brain not able to adapt ?
Anyway, sorry for the long message, I just wanted you to understand where I am coming from, so I have an excuse for why I am calling this done even though I still see possibility to improve 
EDIT : reupload images (I forgot to enable one curve node before saving the jpgs and posting them 
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