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Looks like I need to make a lot of posts . . .
Of course I can share my final design, and explain why I decided to go that way. That is the purpose of this place, isn’t it? 
Actually I plan to prepare and share some kind of guide, but anyway here some brief info.
First of all, the brand new RCWL-0516 comes set up with maximum gain I believe, so we need to tune gain to our needs. Lower gain means less sensitivity of the device, but less sensitivity to electromagnetic noises as well. Tuning the gain is very easy, just solder resistor to R-GAIN place on the PCB, like on picture:
I use 1Mohm, but the less value of the resistor, the less problems with the electromagnetic noises.