This week-end I did model some rocks and debris, then I started to model random props. To test how the light and reflections did react on one of those I imported my ground plane with its glossy rain shader (some areas are more wet than others controlled by different painted maps).
In the end, this sunday launched the animation tests process! I found a way to improve the quality and reduce flaws in my gound shader, it really looks the way I want now:
What I learned : Stop being a beast on values, sometimes lower the value even to a number close to 0 can produce subtle but nice effect on the render. Uncompressed images taken from the above video.