Scaling a Brush Preset

Hello, I have been fighting all day long to achieve this, I am almost giving up, almost because my last hope may be there. Let's see if anyone has the knowledge to help me. As my title says, I need to scale down a brush preset, and by that I litteraly mean it, the Size doesn't cut it, it does not give the result I am looking for.

I would like to have a preset half the size of another, but that gives the same look in the end, exactly as if I would have drawn with the bigger size and resized the picture. To illustrate this, I made 2 graphics, hopefully I can get myself understood :

Here is another one, with less explanations :

the most right example is different from the previous one because I loaded a texture image half the size of the others (same pic obviously)

Thanks for any info that could help me to sort this out.