I don't think it's a bad idea at all! In fact, if there aren't a lot of (or any) singles or people around your age in your church, I think it would be a good idea! Sometimes, we just need a little fellowship with people who are going through the same things we are!
In my church, I am the only person between about 18 and 35. (It's like that in just about every church in my town.) I'm involved in my church, but there aren't a lot of people that I can really connect with because most of them are either in their 40s and married with four kids or are 15 and in high school. There's something special about fellowship with people that are in the same place as you in life. So I've been trying to find a young adults or singles group near me that I can get involved in also, but I've been having a hard time finding one closer than an hour away.