I am leaning towards (i) or (ii). Train shows generally are looking for a more cohesive layout, not just random creations laid out on a table. If the theme is “Winter”, we could work in just about anything, not just town and train stuff (although that is what I will be focusing upon).
Good point about the train shows liking cohesive layouts. I think we could do (ii) a hybrid, semi-collaborative event fairly easily. Keep everything minifig scale (unless we have alpine ski slopes or something in the back for forced perspective), and at least get general dimensions so we can put all the puzzle pieces together. I’m happy to coordinate the layout, if my efforts on the Great Wall and DIG builds were acceptable to yinzall.