Is my iPad not accurate enough or is it the stylus?
This is a limitation of the iPad screen. No stylus will feel like a real pen. Future versions will likely have more sensitive screens. The best you can do is think of it as a giant index card and a fat marker. 

The Wacom software improves the situation a tiny bit by having the zoom mode when writing. You can find other software that allows more zoom, which would make the final product look like a normal page of text, but the act of writing will not be improved.