Most people pick villagers they want based on their own personal taste, although I guess some people would choose villagers that they can 'show off'. Top tier villagers aren't any rarer than other villagers, they are just more expensive which means to get them you either have to be extremely lucky or have a lot of Bells to throw around. I got Stitches when I started up my town, and I like him because he's a cute-ass patchwork bear, not because he's popular. I also got Claudia, Alice and Phoebe, who are all cute villagers, although not top tier. It's all a matter of preference.