Sure, since you seem to like elevation, just stack one reversing loop above the other on what I like to call the "blob" location of your around the wall layout. Heck, they can even be double track reversing loops so that both mainlines can be reversed at each end. You may still have to cut an access panel in the center of the blob (if you place it in a room corner) which would allow you access to both levels of return loops for maintenance and service. There are a lot of people here that will speak against building an access hatch that requires ducking under your layout to reach, but in my world, tough access is better than little or no access at all.
There are people here that help others with designs. Look for posts by DoubleDAZ (Dave) and Ken O-Scale for examples of their work. You could also search the internet for 8x12 layout plans, 8x12 track plans, and double reverse loop track plans to see what might provide you with some ideas.
Chuck
