Actually, if the plane lost all electrical power supplied by the generators (which would have been the case if pushed away from the gate) they would not be in complete darkness. You know that safety demo that the flight attendants do that nobody pays attention to? Well, next time you decide to pay attention listen to the bit about lights illuminating the aisles. Do you think that the FA's or pilots turn these on? Nope? they're triggered to come on automatically when the airplane falls to a certain power level. Therefore the passengers would have had these lights and were not in a pitch black environment. Though at night, it would still be pretty dark.
I personally would not fly China Airlines based on previous accidents and their safety and training culture as a company. But, mechanical things to happen to even the newest airplanes. In fact, wasn't there a certain can do no wrong airline based in Singapore that had a crash based on very poor judgement by the pilots in Taipei? Then shortly thereafter had a 777 in NRT wish tire trouble? Is everyone running from that airline? Is everyone running from AA with several accidents with included deaths in the last few years?
Incidently, on Sunday as we were pushing from the gate we lost our APU generator. Because we were pushing back and had not started the engines we went to the emergency power level, which is powered by the battery. With the help of maintenance, we deferred the generator, started #4 at the gate and proceeded as normal. We have never had a fatality at Mesaba and have an immpecable safety and maintenance record. This proves, that mechanical things break... Our passengers weren't alarmed. Of course we didn't have the melodramatic media get ahold of the minor technical problem either.