I went for Piplup the first time around, and I was really disappointed at its evolution :( They had lost their cuteness. But I really disliked Chimchar and did not really care about Turtwig
Recently however, I saw some nice fanart of Torterra and I grew to love it a lot. So I went with Turtwig :3
I can see your opinion on Piplup's evolutions reminds me of Masamitsu Hidaka (Pokemon anime storyboard artist) saying the real reason why Dawn never evolved her Piplup in the anime was because he claimed that both Prinplup and Empoleon were ugly and unsuitable for contests.
But then again, like you I did change opinions over time, except Chimchar became my fave instead of Turtwig.