I've only played for a couple of hours - all I have to say is wow!
I created a YA female and a horse in CAS/CAP, and have been playing them in AP. I'm not a fan of horses in real-life, but sim horses are just so adorable (as is my sim when she falls off him!). I'm training them both and absolutely love the new career, and the fact that competing (and hopefully winning!) races requires some input from the player and is not just a typical rabbit hole. I haven't interacted much with cats or dogs yet - I'm hopefully going to have my sim adopt a few strays
I really like the new female ponytail and clothes, this EP has added some of the nicest clothes in my opinion.
There's only one thing I can't figure out. When the bladder meter on my horse gets low, he just pees wherever he is standing. Is there some kind of horse toilet (for lack of a better term!) in buy mode? I've looked under the horse category and can't seem to find anything.