I think it's mostly surprising that there is only one Protestant on the court vs. six Catholics, given that the majority of American Christians are some flavour of Protestant and given that there has only been a single Catholic president in American history (Joe Biden would, if elected, only be the second Catholic president).
As for Asians on the high court, Trump seriously considered Amul Thapar and Obama seriously considered Sri Srinivasan (who is currently the DC Circuit Chief Judge, meaning he is the most senior member of the judiciary branch other than the Supreme Court justices). Jacqueline Nguyen had also been floated as a potential Obama pick for the Supreme Court.
To be honest if Biden is elected and gets to appoint two Justices I wouldn't be surprised at all if he nominates Srinivasan (Ketanji Brown Jackson would be all but a lock to replace Breyer).