The X100 cameras have a 23mm lens, which, on an APS-C sensor, provides about the same angle of view as a 35mm lens does on a full-frame camera.
Paired with the WCL-X100, which is a 0.8x wide-angle converter, the X100 captures an angle of view about the same as a 28mm lens on a full-frame camera.
I would like a wider angle of view - something like what you get with a 24mm or 25mm lens on a full-frame body. The X70 looked interesting because, paired with its own WCL-X70 wide-angle converter, it captured an angle of view equivalent to a 21mm lens on a full-frame camera. But angles of view this wide are not possible with the X100 cameras.