1) If I were to rephrase this one, do you engage truth like Schrödinger's cat where everything is considered valid until it is ruled out (pluralism/superposition/ambivalence)? Or do you view things in terms of ideas by default are considered untrue until they can be demonstrated to be necessarily or most compellingly true (reductionism)? Basically, within your agnostism, do you consider the statement "God exists" to be valid or invalid by default? Are you ambivalent or skeptical?
2) synthetic estrogen exposure in the womb has been demonstrated to increase homosexual preference in mice (which includes morphological changes in brain structure during development in utero). Because there is less ability to have experimental control for factors in human development, it is harder to clearly demonstrate the trend in humans. But it is logical that it would reasonably be applicable to humans as well. These people would be "born that way" but for a reason different than simply genetics. Genetics could lead to a predisposition to sensitivity to synthetic estrogen exposure. Take it with a grain of salt as you will, this is just based on a personal perception from papers I've read.
Sexually abused children have shown a higher predisposition to partake in child abuse in their later life. I don' t think that is a disputed point?
And the parasite speculation related to hyperpromiscuous behaviour was based on anecdotal evidence that antiparasitic medication reduced hyperpromiscuous behaviour and homosexual preference in some cases. The nature of some parasites' ability to change the behaviour of hosts to allow for parasite infection transfer and proliferation is likely where the initial speculation came from. This wouldn't be attributed to all homosexual behaviour, only some kinds of hyperpromiscuous behaviour. You can take that with a grain of salt too, it was speculative anecdotal evidence that I had come across at some point.
The main points were from environmental synthetic estrogen and psychological damage from child abuse. Synthetic estrogen pollution is a problem. Child abuse is a problem.
3) Different passages describe the need to understand the Bible from the perspective of the New Testament to avoid a "veiled understanding". If you look at books like Corinthians and Galatians first, you may have an easier time getting a feel for the Christian perspective.
In the same way that pointing an alcoholic to rehab isn't "alcoholo-phobic", or seeking to mitigate unwanted violent outbursts from some war vets with PTSD isn't "war-vet-phobic", or seeking to have criminal pedofiles be segregated from society isn't "pedofile-phobic", the same is true for addressing homosexual impulse as a sinful impulse isn't homophobic. There is no fear or hatred, it is simply an observation within a school of thought that certain behaviours and conditions are not optimal for long-term happiness and wellbeing. You can reject that school of thought, but at the very least recognize that esteeming something as disagreeable or even degenerate does not necessarily come from a place of hatred or fear.
It's hardly the fault of the war vet that they experience PTSD. The question is whether they reasonably attempt to address it or not.
With homosexual tendency, it isn't necessarily going to be the perogative of every Christian to hold nonChristians up to Christian standards. Some might be vocal, but others may have a patient indifference in recognition of the fact that if God wants you on the right path you'll eventually be there.
Even when dealing with idols and the sin of idoltary, the message Paul gave in some of his writings was not to burn down idols and shake the world of nonbelievers, but simply not to partake or encourage those things.
There is a danger for Christians to become highminded, and so the intention is not to shun those that have homosexual urges, but to be mindful of things which are not condusive to longterm wellbeing. But like with a drug addict, addictions and other physiological compulsions aren't wished away by a mere word or voiced intention. There has to be a willingness to change and steps taken to address that physiological drive.
Romans 9:20 speaks to this. The rebuttal is essentially "Who are you to question the creator?" But at the same time, God never gives us more than we can handle (1 Cor 10:13).
To some this can be very unpalatable. There have been many cultural Christians that take a preference for Buddhism and the like that don't have a message of hellfire, etc. Wheat and tares is certainly a topic that comes up in Christianity. Not everyone is saved. But the categorization of who will be saved and will not be saved isn't always certain. God will show mercy to those that He shows mercy.