When a community is founded on principles hostile to Christianity, then the only good thing to do is to wean individuals away from such a community. . Its very anthropology is opposed to that of the Church, so there is little common ground, either spiritual or natural.
You succinctly reiterate my underlying points.
The homosexual community's positions -- ranging from defense to avid promotion -- form a basis of belief that is fundamentally hostile to Biblical Christian doctrine regarding what constitutes sin.
The right thing to do is extract individuals from that community.
There is little common ground to work from.
So, this is the layout of the battlefield -- spiritually and sociologically -- and the gospel of Jesus Christ will prevail in many of these individuals' lives. But only if the Church does not allow itself to take on the persona that the homosexual community is accusing it of having: homophobic, snide, callous, hostile, petty, hateful, hurtful, condescending -- all of these things can be levelled at the Church in an accusatory manner. BUT, the Church must rise above the accusations and, by direct loving action, demonstrate them to be false.
There will always be accusers, but if the Church -- and that means individual members within the Church -- acts in line with scripture, those accusers will be increasingly isolated, discredited, and ingored.