I love Timothy! I think it ages well, and it’s not too popular here in the UK (only 160 in 2012). The only downside is that I dislike Tim and Timmy, which are quite obvious nicknames. Otherwise it’s a great name.
Hm. I like it because I like the nickname Tim, and Timmy’s cute on a kid. But then, the fact that it has “moth” in it really does not appeal to me…. I don’t think there’s any other way to get Tim/Timmy, and I think it’s a solid, well-known but a little underused name. I just don’t think I’d personally use it….