More will come here soon, but I've got a rough half mock up of what the new dialog might look like:
Here is a snapshot of the progress on it as of March 9th. I'm planning on splitting between the hardware itself, and the configuration. The hardware tab will reflect the items actually attached to the computer, and the Configuration tab will have things like Screen/Window mode, key bindings, etc.
Splitting those up should allow for the hardware to be set once, and then many different configurations set up for that one hardware set. The hardware tab will let me set the *real* number of buttons per device, since it appears that the drivers list a few more than are always there. Also this will be where to mark an eraser device as matching a stylus device to make up a single physical device.