L it is hard to make a good pattern from a brush, BUT should be easy make a brush or better a series of brush or a gih from a seamless pattern:
you tile, crop as needed, copy and paste as new brush..
then you do a different crop of the BG that is the original , and/or scale up or down a and/or rotate a bit...and copy and paste as before
May sound boring but i believe could be very addictive...
The only risk is that tomorrow you will maybe need to call some specialist to extract you from layers and layers of barbed wire...
