Just an idea, and I think many will agree with me...

[Zonx]

Photoshop has supported Paths for ages (like since version 7 or maybe 5) for selection and clipping.

CS and newer supports drawing with vector tools directly in the Layers, so you don't need to use the paths tab for this.

Doing lines is a bit of a hassle since Photoshop insists on closing paths if you apply a stroke to one that is open. So you need to use either the line tool or draw a closed path with the pen tool. Then apply a fill color.

Another option is to use the pen tool and just plan to rasterize the layer and delete the extra line used to close the path. In this case you'd set the layer's fill to 0% and aply a stroke using Layer Styles.