By tracing it out with the pen tool, you'll understand the type ligature a little better and this will consequently improve the whole aesthetics of the typography.
As for the brush, I don't use it to draw, only to paint and I only use it with a tablet. Pen tool is better to draw your shape, cos you can still do a transform if you need to unlike a raster paint image. If it helps, hold down shift if you want to paint a straight line. You'll need to click point A then move your mouse to point B and click again.