A fanfiction prompt I had in my mind:

No major changes in the existing plot except for the epilogue.

No weasley bashing.

Just one big change - Ron dies in the battle of Hogwarts.

Ron and Hermione had sex in the text right before he left HHr in the forest. Her shock at him leaving her right after their first time consumes her even more. Harry admits he heard them. Nothing changes. Ron comes back, gets eventually forgiven, but Hermione denies his attempts at more intimacy saying they needed time to figure things out.

After the battle, Ron is dead, and Hermione discovers she's pregnant.

Weasleys think it can't be Ron's since he had been gone for months from the tent. Hermione is pissed and offers no other explanation but Harry defends her which bothers Ginny.

The media and the ministry folks are gossiping about the war Martyr that got cheated on.

Harry takes Hermione in and takes care of her for the rest of her pregnancy, as they both grieve Ron constantly with a lot of angst and sadness involved, but also share playful moments of friendship and solidarity.

When the baby comes Hermione still names her Rose weasley and the Weasleys demand a magical DNA test to comfirm it since they don't want Ron's memory to be maligned, they didn't raise a son who'd do that to a woman without having married her.

Hermione gets the test results and tells them it's a new magical generation that respects love and consent more than the made up bonds approved by the ministry.

Harry is a big big part of her labour and takes care of Rose all the time. Hermione is getting closer to Harry but can't admit it to herself.

Harry has fallen in love but hates himself for trying to inadvertently replace his best mate.

If I could write I'd add some lemon bits of Harry helping Hermione dress if she can't herself, or having her comfortable with Harry being in the labour room with her while she's not very dressed. Or maybe her wondering about her changing pregnant body but Harry sort of drooling over her and hating himself for that. And after he puts Rose to bed he could maybe accidentally walk in on Hermione taking a bath/pumping and being embarrassed about it all.