Ever since I was little, I've always loved animals. And I often use video games to express my love. So I had an idea for a mod that not only adds new animals to Minecraft, but also over halls the existing ones. Here are some of my ideas.
If you ever played ark survival evolved you're probably familiar with the taming system that game has. However instead of beating an animal to death, depending on it's friendliness maybe you can tame it by giving it a favorite food, and keep feeding it or playing with it and eventually overtime it'll become loyal to you. Or if the animal is not so friendly by nature, maybe the player can trap it somehow and care for it in a more longer process.
Once your animal trusts you enough, it will forum a bond with you which will be visible in a menu similar to how it is set up in the harvest moon games. It will be accessible through the inventory menu, and it'll have an icon with the animal's name on it and next to the icon will have an affection level. And the affection level will effect things like for birds egg production, or sheep wool production ect. I also had the idea of on certain levels of friendship. You can preform certain tasks with your pet. For example, At two heats with a dog I can play fetch with it with a stick or a bone. At four hearts you can start training your dog to hunt for you. And at 6 hearts you can pet your dogs belly.
Animals, especially domestic ones, are individuals, both physically and mentally. So why not have a genetics system where you can breed animals together to get certain traits. For example an animal can have different coat patterns, sizes, and other features such as with cows horn size and shape or with dogs different tails.
If you want to help me with this idea please write down in this forum I will create a discord channel where we can discuss our ideas