Well, for starters here's some things you should now
1) Most of us are actually de-churched individuals. According to research by the Barna Instutite, 65% of us have actually made a commitment to Jesus Christ at some point, and among the 35% who have not, 45% have considered it before. The majority of people my age and younger who are not Christians are actually de-churched individuals.
2) Why we left and are leaving the church...
As a millennial, the reason people my age and younger are leaving the church has everything to do inauthenticity in the church. I know many millennials, including myself, who have become fed up with the church because of this. I'd be lying if I said I have not considered leaving the church, not losing my faith, but just not attending church anymore. My generation and those after me have an incredibly developed sense of when something is authentic versus a marketing tool with no backing, we have a very attuned, you know, meter. We cringe every time we see a ministry called "The Well", "Ignite", or (insert supposedly cool and relevant sounding name here), especially when it's obvious they're just doing it to sound "cool". In my experience and opinion, and every other millennial my age who's written on this reflects this idea: we don't want out of the church what the church thinks we want out of church. If I had to list the top three things my generation and younger wants out of church, it would be this: 1) Authenticity 2) Community 3) A God and Christianity that is not watered down to patriotic moralism and escapism (we want to hear about Jesus and how that matters to us and the world right here and now, not the moral decline of America and the world), not "more hip" and entertaining worship and a mini-coffeehouse (okay maybe this one, but it can't be for the sole purpose of attracting people). We don't want to go to church to be entertained, we want to go to church to meet God and each other. We aren't leaving the church because it's not "cool enough", or because we'd rather go out and sin, we're leaving the church because the church has failed and is continuing to fail to actually reach our generation.
We very much sympathize, and may in fact, agree about non-Christians perspectives of Christianity. I think that has a lot to do with the fact that many of our friends are actually de-church individuals. Actually, most people aren't turned off by Christianity, they're turned off by Christians, only 25% of outsiders listed that they're convinced Christianity would be too limiting of their lifestyle and options in life. However 85% said hypocritical (not necessarily just being hypocritical, but not being , 70% said insincere (only concerned with converting people and not the people themselves), 91% said antihomosexual (against gay people themselves, regardless of what they do), 70% said sheltered (out of touch with reality, unintelligent, and old-fashioned), too political (Christians are more motivated by political agendas more than anything else), and 87% said judgmental (prideful and quick to find faults in others, something agreed upon by 53% of young Christians).
Now for the good news, if you want to know where to look at what to do, look at Anglicanism, Catholicism, and Orthodoxy because those churches have what we want out of the church. Those churches are authentic, they have a strong sense of and a welcoming community, and preach a Christianity that matters to us and the world right here and now. They aren't doing anything special to entice us, they are just being themselves and that's what appealing.