The episode Data's Day takes place on Diwali.
Hm, I had either not noticed, or forgotten that. A minor throwaway line and no actual celebration is shown. And you are correct in that there is no indication that there was any religious significance to the event.
What the Nazi doctors did wasn't science. They were atrocities. True science respects human life.
Never seen (or read) Frankenstein, I take it?
I'm sure there are. But it would be difficult to work that into an episode.
I'm sure that's a joke.
'Cause they've already done it, just not with humans (and despite Leonard's protestations to the opposite, Starfleet is still a homo-sapiens only club). Consider how frequently Kira was interrupted while praying at her alter over the course of DS9. Or the near infinite number of times some inane 'funny' scene was worked into an episode that served no purpose other than to make the audience roll their eyes. There was opportunity and time both.