Sometimes, I have let the dds name them, and I even let the dgds suggest some names. In the past few years, I have done most of the naming, but dh did name Sparky because he was such a spitfire as a new kitty.
Answers to questions:

1. Both Kaethe and Maike were names that were hard for others to spell and some to pronounce. Make was pronounced Mike, and Kaethe was pronounced Kayta. My co-workers used to joke with me about hard they were to spell and pronounce. So, when I named Kenzi, I thought there would be no issue. The pronunciation was fine, but they never could get the spelling right. By the way, I changed the spelling, but she was named after the main character in Sue Grafton's series of books.

2. We have used human names - Claudia, Beau (Beauregard, the Southern general), Thomas, Quincy, Ethan, Simon, Peggy, Sophie, Heidi.

3. I don't think we have ever had a name anyone disliked.

4. I loved both Maike and Kaethe because they were unusual.