Whether a vessel uses the new touchdown points with dampening or the old ones without it is determined by the code in its dll, so no, there's no such option.
I am not sure. Most touchdown point are a triangle. But I am not sure if one can get the exact point where the gear would come into contact and adjust to raise/lower. The area where landing pads are are not even.
On 2016 ships have suspension. So they sink due to mass and gravity. It's possible to balance that out for one planet. But not for all. There's no hard colision with a surface in 2016.