I personally like to start on the lean side and gradually go richer just until it runs well (good response, no hesitation) but I have a wideband O2 sensor and know how to be careful if things are too lean (keep your foot off the gas!). I'd put it at 14:1 at idle and 15.5:1 at cruise and see what happens.
13.6:1 and 14.3:1 ARE rich... all modern cars with cat. converters target 14.7:1 at cruise and idle but that's with port fuel injection, the EZ-EFI is throttle body right?
