Now that it's been a while since Cats&Dogs released, I've made up my mind about it and I have to agree with the OP.
Just recently I had my sim move to Brindleton Bay and get a vet clinic in preparation for Seasons. I wanted her to be a vet and also have a garden on the side, that would later on bloom into a full on farm with a multitude of produce, dogs running around having the time of their lives being close with nature and having lots of room to play.
First of all - no such thing possible. Pets don't care about their living conditions. Whether you keep them in a tiny apartment, a huge mansion, or have them be outside most of the time doesn't matter. Pets can't do much outside, they don't interact with nature properly besides dogs searching for collectibles and scaring off the birds. Dogs have no reaction to open spaces. Have you ever seen a dog that doesn't get excited once its let out to run freely in a big garden or a beach? It's ridiculous how little pets can do outside of their home.
Second... I wanted my sim to have a deep bond with her dogs. What's a deep bond when your dog can't even sleep in your bed? I know some people don't allow that, but let's be honest, most of us do and we love it! Its nice and comforting. Dogs not being able to go in sims' beds is so immersion breaking for me I mostly just own cats now. I wanted my sims' dog to be her best friend, a companion, and seeing the dog sleep by her bed instead of right next to her, despite the other side of the bed being completely empty just breaks my heart.
Pets act up and without the controllable pets mod they keep running away because you can't possible keep an eye on them all the time to make sure their needs are fulfilled. Lose track of your cat for 5 minutes trying to have your sim do something interesting - bam. The cat runs away because it feels neglected. This is something everyone feared even before the EP came out and we were right. Not being able to control pets by default makes the gameplay tedious and annoying. I don't want to micromanage my pets all the time but if you want a cat or a dog in this game you pretty much have to say goodbye to other gameplay aspects.
This EP lacks heart and soul and most importantly - balance. In previous iterations I could have a pet and have fun with it but I didn't have to focus on said pet entirely. The pet would blend in with the household in a realistic way. They were always there for me to interact with when I felt like it but I wasn't worried all the time something bad will happen to them as soon as I play my human sims. In 4, pets demand constant attention which gets old fast and just makes me tired of playing.
On top of that, the world is small, there are no new hobby activities, just nothing to do. The vet career isn't much of an improvement over the rest of businesses in the game. I'm so upset over them simply ruining one of the best expansions for the sims that people anticipate so much. I wanted to love it as much as I love my cats and dogs in real life, but I just can't. It was a waste of money.