Ethics (also known as moral philosophy) is a branch of philosophy which seeks to address questions about morality.
A Muslim, Christian, Jew & Atheist can not have a discussion on ethics b/c they do not share common philosophies.
As a Christian, there is no way I can give you any Scriptural information that will seem ethical to you. -- Yes, we can agree on common Earthly morals. But it's impossible to discuss spiritual matters with a non-spiritual person. At least not to any degree of satisfaction by either party.
That said. Don't take the arguments you may have heard about Christianity out of context. (If you are referring to 1 Corinthians 6) Note that the abstract concept of "homosexuality" is linked as being the same as "coveting." Coveting is desiring something that you are not meant to have at this time. Do you have any idea how many MORE Muslim, Christians & Jews together are more guilty of this than the entire global community of homosexuals?!
I agree with a previous answer. The point of Scripture is about Salvation.
Everything listed as a sin is NATURAL behavior. What Scripture tries to help us all see & do is to rise above our natural instincts in the here & now so that we may be perfected in the super-NATURAL. Aspiring to be spiritual beings.
Don't focus on one aspect of what is being taught. I am a 7th day Sabbath keeper. (Not a 7th Day Adventist) But this is not my RELIGION. I don't need to focus on this ONE commandment, nor should I or I will miss the message of love & grace. I don't even keep the Sabbath correctly. Nor can I in this life. (There's a lot of rules. I will never be able to keep them 100%, 100% of the time.) But it does not mean that I can not strive b/c in doing so this deepens my relation with my Creator.
As an Atheist, it's not possible to desire a deeper relationship with your Creator b/c you believe/know that you have no Creator. Therefore all of the messages in Scripture will be nonsense to you.
Punishment is reserved for those whom know/knew the Creator God and denied Him. I don't think that you fall into this category (yet). Read The Book. Everyone gets their fair chance. Our human version of "fair" is not on the same scale as G-d the Creator. We seem to think it's if we passed by a street preacher yelling "REPENT" and we didn't, then we lost our chance. That's not LOVE from an all-loving G-d. B/C I can beat that type of love as an human parent. When I tell my child to apologize, even I know they will not do it on the 1st request if they are mad enough.
The love for you from your Creator transcends the greatest love you can ever know on this Earth from other humans. If you're not feeling the love from any religious sect, then G-d's not behind whomever is talking to you. G-d has a way of correcting & reprimanding those He loves in a way that POURS love all over you. It's overwhelming that you can be corrected & feel so loved at the same time. If that has not come your way, then it's my opinion that you have not been given your "fair" chance yet. Don't let the "homosexual" thing get in the way of receiving that love.
"Sin" literally means "to miss the mark." At my age, I'll bet I've got you beat on that scale way more than you could imagine. But I'm not focussed on that. Keeping an eye on my sins, keep my eyes off of G-d.
It's good to look at what is holding you back, but only to make corrections to advance on your course. I think all faiths can agree to that.
If you ever decide to seek Him, do it while He may still be found. You don't even have to change your life to go looking. (That's His job.)
One day you may decide to live your life AS IF there were an all loving being that cared about you more than His own life. No dogma. No organized religion. Just a personal relationship where you love b/c you were first loved. THEN you can ask Him directly about how to live your life. A lot of those answers will be found in Scripture, BUT not until it's time for your eyes to be opened to each new thing. So if something doesn't make sense, ask about it & keep asking. When it's important enough for you to understand & follow, then it will be made known to you.
Forget about these nit-picking debates. They will only annoy you further.