Watched The Host tonight and the trill are so different in TNG than they were in DS9. I wonder if there is a logical in universe explanation to the discrepancies, like using the transporter would kill the symbiant. As for the end, everyone seems to always have a problem with the ending, but I'm not sure if TNG would have been capable of covering a subject like that. They tried in the next season but it seemed to just take the easy way out. Unfortunately, the concept of LGBT was really taboo back then, much moreso than it is today.
I do feel like Crusher's reaction was pretty much normal from the episode though. We get a character who loses the person she loves, that person comes back as a fellow officer, and then that same person comes back again as a female. That's a lot to take in, even if the plot logistics leaves a lot of questions, such as why didn't Crusher know who Odan was when he got on board.