I will start.
Francis.
Loathe it. Couldn't say why really. There are no bad connotations - it's neither 'chav' nor 'toff'. It's not made-up or too-trendy or old-fashioned. I couldn't say that the sound of it is awful. It doesn't remind me someone who bullied me at school. It's not even boring. I just fucking hate that name. Whenever I am introduced to a new baby called Francis, my reaction is always: "But why? For pity's sake, why? Out of all the possible names available, you chose Francis? You have some seriously terrible taste there, people." "Gosh, how lovely."
Same goes for Christopher. And Jenny.
Perfectly inoffensive names. Could give no good reason for my antipathy whatsoever.