Around-the-room!
I have had both Island and R-T-W types during the past 30 years[now dismantled] and found far more enjoyment with the round-the-wall. Curently I am reduced to building a 9 x 16 "Senior Citizens" layout in a 9+ x 19 attic space. One benchwork side is 42 inches wide, admittedly a "reach" to work at the wall unless standing on my toolbox, but necessary space for the dual main and the Service Yard I wanted.. The other side, to be the "Villiage", is 36" wide. I have a dual track mainline with 072/084 one end and 084/096 on the other.
I have a center space walkway/workway at a little over 30"wide, the benchwork is 42"high. To avoid a "duckunder" I recycled an old Jim Barrett designed, piano hinged "Drop Section" from another layout that closes and opens on spring-loaded catches that I activate with an underneath lever. The Drop Section is located in the dual 72/084 curve 3' back from the room entrance. [A "Lift Bridge" would also work if made wide enough to accommodate the curves]. The layout's far end corners have triangle openings that can be lifted out but will be mostly permanent. For that reason one corner is to have a Textile Mill and the other a Sawmill/Lumber Yard---both have spur tracks off the straight at the beginning of the 096 end curves.
Because topside room is scarce, my power center is mounted vertically on a wall under the layout near the entrance. Up top controls are a Cab 1, track schematic with SPST toggles that control the 17 Tortoise turnout motors,a mounting of panel meters and Power Guards. The bench worktop here is plexiglas so I can see the LEDs on the PowerHouses,Command Base and TPCS mounted below.
My sidewalls are only 13" high, from top of benchwork to beginning of kneewall rafter pitch. I painted everything above the bench sky blue and I am installing 13"h x 8' long Masonite panels both sides with industrial velcro so as to remove later for backdrop treatment. Probably have some bulding fronts and some mural painting while the panels are off resting on an easel. Gargraves Flextrack is laid, part of railsides rust painted and track glue-ballasted and wiring is completed. however The layout is in total disarray as I deal with various projects including the velro-ed panels and corner scenes.
Small area to be sure and no long coal trains will run. But a layout I can maintain and run trains on and best of all, don't have to duckunder ["crawlunder" actually, at my age].