What's the worst expansion pack and game pack and why?

For me it's Cats & Dogs. I don't like the focus of the pack over all (veterinary career, sick pets, expanded pet CAS), but there are some issues that really bother me:

In rotational play pets are often sick when you get back to the household. This feels like an undeserved punishment and also takes away from the time when pets actually get sick. Pets should not get sick while I'm not playing them.

Walking a dog takes incredibly long time in some neighbourhoods, even just a short walk. All the walk lengths should be re-estimated.

When pets are bred the puppies/kittens end up being completely copies of either of their parent. There should be variation in the colour at least.