What I see is that I can set the grid size in pixels, but the grid will always be square rather than rectangular (like Facebook ads images)
I cannot set different values between base and height.
Now I solve by creating a vector grid in the Designer. I import it and fit in my artboard. But it's too time-expensive.
But if exist a short way to do same result, I'll like any suggest
Still with regard to adaptable grids, it would be good to create a predefined grid for the rule of thirds, the golden rule, and all the rules suitable for photographic cutting (a bit like what happens in lightroom)