First off, I would just like to point out that the people who say it was better before it was owned by Owlient are misinformed. I was on the game when it was only 6 months old and I can tell you Owlient was the ORIGINAL company. The problem is that it's now owned by Owlient through Ubisoft, making Ubisoft the main source of the problem.
Before Ubisoft bought it, it didn't heavily rely on spending real money to be at the top of the pack. Today, you either have to be someone from the very start of the game that never restarted your account or be a frequent pass buyer to get up to the top.
You've also got divines and special horses that are honestly so common now because a new one comes out every month that they're not all that special anymore.
The graphics are a little too focused on being realistic that they're actually losing their touch on reality. It was far better when they were cuter. They still had a touch of realism, but were also cute.
You can only breed donkeys and drafts three times in their lifespan, no more. Honestly, if there was any kind of species that such a restriction should be put on, it should be the unicorns so that they can remain special, and remove the probability of getting a uni foal to make it a guarantee if they were to go that route. Donkeys and drafts should be able to be bred far more frequently.
The karma system (both old and new) are totally hackable. Honestly, if you're a pass buyer and don't have anything to lose, with the new system, you can just restart your game and boom. Back up to 10 karma instead of whatever number you were dropped down to. With the old system, if you lost karma, you could just buy some passes and regain them. The karma system doesn't do squat to tell you who's a bad and who's a good player. I've even had a friend that got dropped to 5 karma points and suspended for 3 days because she posted on her profile page that she wouldn't advertise the game to anyone else because it was going downhill, and Howrse marked that as an attack on them. She didn't bash on them or anything, she just said that she didn't approve of the changes being made and thus she wouldn't tell her friends to join it.
There's also the fact that trying to report someone now, can often backfire. Howrse rarely looks into the details of the situation anymore and just offers punishments straight up because someone reported someone else, and often times for something they didn't even do. You can tell someone that's begging you to sell them one of your horses no, and that's all you have to do is just tell them no, nothing else, and they can report you and you will get in trouble for it, ranging anywhere from a temporary ban from the PM system to losing karma. It's ridiculous.
The new rules are also becoming a bit absurd. They say it's to demote cheating and avoid becoming a game known for its cheating, but in all honesty, I think it's simply because they're tired of having the younger kids on the game whine about how some of the older players have more experience and knowledge on how to get around some of the road blocks in comparison. Seriously... it's called Google... you can learn just about anything from it about almost anything you want, including little tips and tricks about online games such as Howrse.
They used to have wonderful things like Riding Levels (which pretty much required you to learn a couple of things about horses so that you could improve your game experience, thus making the game educational back at the time,) quests, all sorts of wonderful and fun things, including diseases and medicine for diseases, things that made it challenging, that made you have to work to keep your horse farm productive and alive, that required you to actually think rather than coast, that got taken away because lazier kids complained about it being "too hard."
This game also has changes every month. EVERY MONTH! I am not even remotely exaggerating. Some are rule changes, some are play changes, some are changes for special accounts... but either way... way too many changes. It'd be one thing if they were bug changes, but they're not. They're often pointless changes that didn't even need changed.
I would not recommend this game. I only still play it because I have dear friends on there that I don't wish to lose contact with. If you want a horse simulation game, I would recommend Equiverse or Horse Eden Eventing. Those two games even include genetics for breeding, unlike Howrse.