Yes, everything you’ve said is the official position of the catholic church. But the question was…what would you change?

I don’t agree with the church.
You say it’s because the apostles weren’t female. I bet you Jesus called women to get up and follow him too but a mother’s love is probably the only thing that could stop a person wanting to follow his command. If he called women they couldn’t go, because their children needed them and in that time and age, it’s likely husbands wouldn’t allow it. That doesn’t mean women wouldn’t have made excellent apostles.
Jesus also taught love, and he never specified that it was wrong to change your sex, he just said marriage is for a man and a woman. What’s more, Jesus was a man too, as much as a God, or we would cheapen his sacrifice by saying otherwise. Why else did he cry blood the night before he was crucified? He was afraid, because he was human. Humans make mistakes.
But God didn’t create two genders did he? He created men who feel like men, women who feel like women, women who feel like men, men who feel like women, men who feel they’re animals inside, and people who feel they have no gender whatsoever. So he made binary bodies, but he didn’t make binary minds or hearts. Our challenge is to see past our own preconceptions and access pure love, forgiveness and acceptance of those individuals, down to letting them do what they wish with their bodies.
Gay marriage…well obviously the church opposes that, because of the children issue. Plenty of kids who need loving homes, and you may not think it counts as love but I reckon a lot of people would disagree with you as they bring up happy, healthy children who have two moms or two dads
Er…hate to be crude but the sex organs work fine for it LOL. They’ve been working fine since long before the bible! Plus that is cultural, it’s about making babies in a time when carrying on the name was vital. So obviously the bible writers put that in there to protect patriarchal lineage.
And I’m pretty sure he meant spilled his seed to avoid having a child, which is different to just spilling seed. That happens during wet dreams and that’s not sinful is it?
On the last point I utterly agree with you. Contraception has created a mindset where sex is free and women (and men) can be objectified as body parts for gratification. That said…you could take the pill to control PCOS, without the intention to prevent yourself having kids, because the pill can fail, and God works in mysterious ways…and you could take it without having that false belief about intimacy too.
Contraception can feed into that belief, but it can also be used where that belief isn’t in place. Obviously, not everyone who uses contraception treats sex as cheap and easy.
But I will grant that contraception is making it easier for the unscrupulous to be unscrupulous.
Anyway, that’s why I’d change these things. I get that every catholic in the world would disagree with me, but that ain’t my problem LOL. I see a different world I’m afraid.