I couldn't stand Feraligatr's appearance when I was younger. I kept my starter as a Croconaw in Crystal (and unless if the battery died, he would be like, level 77). I just love Croconaw too much. He looks like a boss but he's still pretty cute, haha.
So.. I would have to vote for the Squirtle line since I love all 3 members of the Squirtle family. :P
For nostalgia reasons...
