There are a variety of questions these raised, and I will do my best to stay focused. The things with which I am concerned are the issues about Christians presenting themselves to the world and the targeted importance of homosexuality.
I will go in reverse order, as I frequently do. I think that I must acknowledge that there is rather explicit Scripture to describe homosexuality as less than ideal (Mark 10:5-9, Rom 1:24-27, 1 Cor 6:9), to put it charitably. However, there is no shortage of other behaviors, much more socially acceptable, that are fall into similarly explicit categories. That Mark passage is pretty specific about divorce as well; but that is a touchy subject – I myself am a product of divorce: my mom is my dad's second wife. Being irresponsible with your resources is also very clearly considered sinful (Matt 25). Not taking care of “the least of these” is also a direct command from Christ in that chapter.
I could make this list of issues that come up that are not addressed with the same fervor as homosexuality gets in the media and is also explicitly dealt with in the New Testament. That is not to imply that homosexuality is some sort of lesser sin, rather it is to say that there is no distinction between severities of sin. We are all failures to meet God's expectations; that is why Christ came in the first place. I do not think that we should give homosexuals a pass because of this, but abject condemnation does not help – there is no doubt in the public consciousness that there is a disapproval of homosexual behavior by the church at large. If the church speaks out in an effort to help people – not necessarily to 'reform' them, but to really meet their needs on a personal level, whatever they are – then that is different. Telling someone that they are going to Hell is rarely constructive.
Our messages, at least, those to whom the media pay attention, frequently portray negative messages – Pat Robertson, James Dobson, Jerry Fallwell. At least, those are the messages that get to the public. The totality of their message is almost irrelevant if it does not get out, sadly. (There is, after all, a Biblical Mandate to spread the good news. If the dialogue gets hung up on all the kinds of things that Christians disapprove of, then we sound like stodgy grandparents with arms crossed and brows furrowed looking down our horn-rimmed glasses rather than messengers of an Almighty and loving God with the path to salvation out of a dying world, and our message is ultimately discredited.)
I cannot say that I have a great answer to how we should look at some of these behaviors that are considered sinful. The very nature of the Law was that it pointed out that satisfying it was unachievable, demonstrating our need for God in our lives. We all fall short of it. That does not mean we should not try to pursue a life concordant with God's Will, I do think it means we need to use some perspective on the matter, though.
We also need to be aware of the fact that our actions matter. People are watching us, and if our words say “God is love,” but our actions say, “but not for them,” then we fail. We fail each other, we fail the people who need help, and we fail Christ. As it stands, homosexuals are a marginalized segment of society, and those are the very people to whom we are called to reach out, do not forget.
I did not talk specifically about the issues surrounding the two cases I mentioned at the beginning because I do not want this space to be used for political discussion. I do not believe there is Scriptural support for Christians creating a government that enforces rules making it illegal not to be Christian, and is important not to forget that, too.