I can only address your last point because your numbering is off and I cannot parse it.
Teenagers being sexually active, if it's done safely, is a net positive. Look at the whole incel stuff. A lot of people who didn't have romantic and sexual experiences during their late teens end up being angry at society, and at times violent. If Elliot Rogers had been able to get laid, he wouldn't have gone on a rampage.
1. They can now; it's been a thing for a few years, it's just expensive. Isn't science great?
2. Almost always true at this time.
3. Statistics do not bear this out.
4. Paralogism / non sequitur.
5. Is this descriptive or prescriptive? If it's descriptive, your description is counterfactual. If it's prescriptive, you'll have to make a case for it.
6. Statistically it turns out that kids raised by lesbians do slightly better in school than kids raised by heterosexuals. How do you correlate this with that?
7. You're starting to repeat yourself.
8. Trivially counterfactual: you're discounting the obvious (two people have more time to dedicate to children than one person). In fact, this makes an excellent case for raising children in a poly household or in a traditional extended family.
9. Again, no. Statistically, you're best off being raised by lesbians, it turns out. (Look it up!)
10. Homosexuality was removed from the DSM in 1973.
11. Citation needed. Your one assertion can't invalidate decades of study of families who practice adoption.