I own a small farm with 6 horses, 15 goats, 7 pigs and 30 plus chickens, and feel the game horses and other animals could be more realistic in this game.
Fact 1: Horses can and do swim. They often paw at the water at first like slapping it with their front hooves, but well trained horses walk right in. When the horse can no longer reach the bottom, they start to swim. The rider dismounts while keeping hold of the saddle horn and swim alongside the horse pulls the rider along.
If you can't make them swim, at least make them lighter than 100 pounds. I have never had to carry a horse on my back while swimming. No one in real life ever has.
Fact 2: People can shoot guns, bows, slingshots, and crossbows while mounted on horseback, even when the horse is running.
Fact 3: Rangers should also get cavalry ability to ride a war horse. The point restrictions otherwise makes this more difficult than it should be.
As for goats and pigs, They best ratio for a barn is 1 male to 15-20 females. The males over 1 year will often kill each other if not separated. The single male will breed all of the females. Any more males and you are asking for trouble. There will be blood.
Animals also need WATER. Chickens will start killing each other without it. Goats can go a week without it but pigs can't. The have no sweat glands and need water to digest their food and keep cool.
I hope this helps, I am happy to send pictures and answer questions if you are unfamiliar.
THanks for developing such a great game!