How to achieve this low poly lighting? Ok, new to 3D lighting overall here and Ive gone through every Blender lighting tutorial for low poly like PigArt, etc but can't achieve this lighting/rendering - low poly so that the triangles are defined but more glossy:

https://dribbble.com/shots/3471048-Xbox-clubs-image

OR 

These are different from just a basic sun light, the world set to white color and everything that is described in tutorials. Ive tried setting materials to glossy but still can't get this.

How can I do this? Any good tutorials?
I've looked at the other works from Alex Pushilin and here is my attempt to reproduce it.

Setup is very simple. One Sun Lamp with warm color and small Size and RGB Background (this one is with Spherical Gradient). 

For materials I've used Principled Shader with Roughness - 1.0.

Most important thing here is to use Filimic Color management. I've used Look > High Contrast with a little correction from RGB Curves.

Also I've lower a bit Saturation in Compositing. 

Every probably will need a little bit different settings.