Here is an idea for an 8X14 layout that fits in an 8X16 space. It is based on five 2X6 tables/modules with one 2X2. It has two lift-out bridges at the entrance to the layout. There is room for a door on the lower right into the room from either of two walls. Access and reach is excellent for the entire layout. The outer route is O-60 to handle O-54 locomotives. The inner route and the two spurs are O-48 minimum, so traditional locomotives and cars will look good going around these curves. There are industry spurs scattered around the layout, and there are O-60 cross-overs between the routes. One long spur could serve as a staging/holding track for a third train on the layout, taking turns with the other two trains without having to take trains and cars on and off the layout to change trains.
All mainline turnouts are O-60, with some industry spurs using O-48 turnouts. All spurs have lighted Fastrack bumpers. A run-round track is included. There are some industry ideas, along with one tunnel.