/ic/ - Artwork/Critique

I know this has been asked a lot but how can I keep from the opacity building up when multiple strokes overlap? I'm using Krita with the "wash" painting mode. I'm basically looking for it to behave as if everything was one stroke, so I can't darken part of a stroke just by going over it with another stroke, no matter how light.

In other words, I want it to behave like left all the time, things only darkening the harder I press down. Right is just awful. I've tried seeking google's help, I'm really not sure what to google though because nothing useful came up.