I'm not understanding what you mean by angle. All of the brush strokes look perpendicular to me. The spacing around the stroke is a set amount and whether the brush is up and down or on a curve, that space remains the same.

If you want the brush to curve as it goes around the bend, you would probably have to use the dynamics and do one stroke at a time with the angle setting so the brush will turn. Other than that, it looks okay the way it is now cuz they are all spaced evenly as O says.

What you want, cannot be achieved with dynamics.
I think, what you need is a brush pipe.
As english is not my native language, please look with your preferred
search engine for brush pipes in gimp.
There you can define layers as part of a brush pipe, which will
change its angle by painting direction.

Use the "Track Direction" dynamics (they just map "Angle" to "Direction").



Works best when using a path: