Yes, cattle can become very much a hobby. I knew friends who started out with 3, and after several years (not sure how many exactly) they had a herd of about 15! She could not butcher then, they were her babies. LOL Lucky is a very lucky guy indeed! My former father in law always had Herefords, and first fresheners were bred to Black Angus, because they were smaller, and babies were easier to be born. Herefords are larger cows, I guess. I just like their coloring. Black white face babies are so adorable, too.
Yes, at the price your local high school charges for koi, you should definitely get some! Weren't you thinking of getting some mosquito fish first, then the goldfish, then the koi, or am I remembering someone else's post? Once you have fish, you will be staring at that pond for hours at a time! And, lilies, oh, they are so much fun to watch grow because they grow so fast!
Remind us what type of plants you bought and are waiting for, too!