Corrected entry: George tells Ada that he can't read, yet later she burns a message into a piano key to be delivered to him.
Corrected entry: Though not noblemen, it's clear that Sam Neill and Holly Hunter are at least upper middle-class people. In the mid 19th century a woman with a bastard child would not have been able to hold her good status, she would have been considered a whore and not suitable for a man such as Neill to marry.
Correction: The wilds of New Zealand is not exactly the same as the high society scene of London, which is why her father was able to find someone there who would marry her (Keitel). So it's not too surprising that there is a second person there willing to marry her.
Correction: He did not read the piano key, a young girl from the local school read it to him.