The cable in the picture is as tight as possible. That's with the shorter link wire. I tried the longer one and reduced the toe a bit, and it's getting closer to where I want it. The lever still feels a little loose, but at least I don't have to pull it all the way to the handlebars anymore.
The housings I'm using are the same length and curve as what I've always used for calipers on road bikes. Could that be affecting the setup I have at all?