Thank you for your thoughtful reply. I'm working on a MY Little Pony fan fiction in which the main character (who ascended to a leadership role a couple of seasons ago) is being let in on the secret of their world being flat. A flat earth model makes a lot more sense than a globe model within the context of that fictional universe, but the show has globes in it, including one in a stained glass window next to the throne that's shown in the opening sequence.
This creates an interesting contradiction.
I think the show developers meant the window as a symbolic representation of the royal's power over their world, which makes it interesting. There's a surprising amount of depth between the lines of that show which is fun to explore with different writings. The G rating of the show keeps some canon storylines from going too deep of course but they're basically human equivalents.
The main character is now considered one of the four ruling elite whereas before she was simply a student of one of the others. As such, in my story, she's going to be let in on the secret that all of Coltpernicus' ideas were complete nonsense.
I'm having a good time writing it but even if it's just fan fiction I still want to portray flat earth in a respectful way. It might help some of my readers think outside the box a little bit even if it's not something they would seriously entertain for the real world.
I want to put as many credible sounding flat earth arguments into the story as I can without making it too dry.
I don't like the idea of universal acceleration because to be a little blunt about it, that sounds stupid to me.
I think that if the flat earth model is correct, then I would go with a motionless earth. The main problem with gravity is that if it's true as science now understands it, it would crush anything the size of the earth into a ball. So a flat earth has to either have no gravity (but something to account for the directionality of the sinking/rising) or a gravity with different properties than is currently understood.