Greg wrote

So almost all of those look like it might be best to just not have an output way. In general I worry that renderers (and mkgamp+garmin_firmware is) supporting confused tagging reduces pressure to fix it.

Those miscellaneous highway types could be treated like raceway > highway=service platform > railway=platform abandoned > highway=track crossing (should be a node, so no line) bus_guideway > highway=service I agree to leave other highway types not rendered.