Best thing to think of, is the ones that appeal to you. If you are creative, you can put any pokemon into that zone. My Patrat was changed up a bit to look bright, my Staryu was made to look old and dignified, and my Duskull and Purrlion were made to look evil and conniving. Why don't you give me the top 4 first evo pokemon you dig.
Also think of things like, do you want to show hands doing things, do you want them bipedal or are you cool with them on all fours? I tend to choose only ones that walk on two legs, however, I modified Purrlion to walk on his hind legs only, like pikachu.