Brush curser fades to almost invisible when over mid tone areas

[#1]

When I'm using pretty much any brush for painting, healing brush, burning, etc. my brush has a solid a white outline when over a dark area of an image like hair, clothing and other darker areas but when I go over a mid range area like a face, it seems to fade to the same brightness as the image area I'm working on making it almost impossible to see. If I move to a darker area, it changes back to white and I can see it again...untill it blends into a mid tone area again. Is there a reason for this happening? I'd like to have it stay the same color/brightness regardless of the image I'm working on. Any thoughts?

It would be nice if there was a way to change the color of the curser to a different color like bright fucia so it would always be able to be seen too.

[#2]

When I'm using pretty much any brush for painting, healing brush, burning, etc. my brush has a solid a white outline when over a dark area of an image like hair, clothing and other darker areas but when I go over a mid range area like a face, it seems to fade to the same brightness as the image area I'm working on making it almost impossible to see. If I move to a darker area, it changes back to white and I can see it again...untill it blends into a mid tone area again. Is there a reason for this happening? I'd like to have it stay the same color/brightness regardless of the image I'm working on. Any thoughts?

It would be nice if there was a way to change the color of the curser to a different color like bright fucia so it would always be able to be seen too.