Don’t think of them as a “Big” model…think of them as a Diaroma - several kits that make up a “Big” display… Make it to where the wings are not permament - the same with the fuselage, several sections put together, This way if something does not come out right - jus show part of it and the rest is under construction.
Also, the sections can be carried to shows are club events without having to have a pickup.
1/72 C5 wing’s I’m working on is nothing but a scratch built model that I’m focusing on only. If they come out right then I’ll add them to the Fusleage, if not…I’ll jus mount them to something that will allow the the wings to be a model on their own.