My Mac was an only kitty for the first couple of years I had him. I really wanted another cat, but Mac is definitely an Alpha and I did not know how he would take another cat in the house.
To make a long story short, I was in Pet Smart, looking for a scratching post, when I saw a cage full of lovely Siamese kittens. Ming stood out because of his beautiful coloring and sweet disposition. I brought him home and Mac wasn't any too happy about it, but he adjusted. Now, they are not exactly best friends, but they basically get along. They even sleep next to each other at night sometimes. Ming is my son's cat and they love each other dearly! I love having two so much, I talked my boyfriend into doing the same. Now he has two and loves it! I think most cats get along, if you give it time. I think Paizly would take to a kitten more than another grown cat. If you decided to try for two, a kitten may be nice.