Wow 8 tracks, that is a lot! we have done well with 4 tracks, two shinkansen and two local/express/freight. we just try and switch out trains often if we can to keep things mixed up more. having sidings, passing tracks and yards lets you display the trains as well as quickly pull them out to run them and gets you a bit of operations as well.
i like the idea of a unitram layout with a station then suburban wandering line to another station. could stretch it out of over a few tables and make it meander. the very cool thing about japan is that city urban/suburban/industrial/rural/wild and back is pretty fast. watch many of the trip videos from japan and its startlingly fast, almost looks like compressed layout scenery at times, but makes it perfect to model. ive had the idea for a long time now to do a modular 1 or 2 line point to point that just meanders with small stations in between and just model these transitions back and forth like that.
again I would caution to try something simple out to begin with. Its a big commitment to doing a larger layout for shows like this. We poured A LOT of time and money into the jrm layouts over the years and we usually had at least 5-6 people pretty active at any time and have 4-6 per folks show up to help with shows. few logistical things to think about
- transport - make sure you have enough transportation volume, sound funny but its amazing how fast all the stuff piles up! jrm layout now takes a full mini van to transport of 3-4 hatchback/station wagons. this has actually been an issue trying to make the layout as big as possible but also fit into our potential transport. thats why we did 1m long x 0.5m wide bases as that was the max to easily fit into the back seat of a compact car if needed. layouts like ntrak with their 4' long modules can be difficult to transport. smaller modules are great, but you end up then needing a lot of them to try and fill a larger space. its a real juggle of tradeoffs!
- storage - where to keep all the stuff when not at a show. this actually is also an issue for us as only two of us have room most of the time (and also logistically near to meet up for loading and such) to store the layout. it can become a bit of a burden.
- manpower - it takes quite a bit of effort to schlep stuff to shows, set it up, run, tear down and get home outside of just building the layout. so far its just the two of you, you dont want to burn out early on this.
- resources - can you get all the track from what you have or will you need to make a big investment to get the critical mass going. i ended up loaning the club a huge pile of track for a year or two until we had the money built up from doing some shows to buy me out.
- time - it does take out a lot of time from your own hobby time to work on the club stuff. works well here with us as most of us dont have large home layouts yet so we have been willing to put a lot of our own hobby time into the club layout. but i have slowly decided to back off doing a lot of work with the club layout and attending all the shows full time as i realize it has taken away a lot of my time from my own hobby stuff.
Just things to think about, they sound minor but actually are pretty big in the overall equation over the years on doing the shows. there are solutions and compromises for most all of them if you think of them before the bite you in the a$$. not saying dont do it at all, just cautioning to maybe try the waters with something simple and easy and then if you guys are super into it then scale up to a full modular or sectional thing.
unitram would be perfect to setup on the fly and maybe test the waters with and see if its fun for you.
another idea we once had for something quick was to do some sort of medium sized modules to do a big loop or square. these would be local/express/freight, lots of scenery and have good transitions of scenery. then have simple modules behind them with elevated viaduct track. almost no scenery on these just generic bases to bring the height up to the front modules. these would have shinkansens and then we could add in a station or two as we went along. idea was to have something modular but break up not having the viaduct and the regular tracks on the same module as it got big and complicated to do both. this way either could do a slightly different path and vary if we wanted it from a longer loop to a bit square donut shape or even wildly different by having an intersection module where the viaduct modules could come out to the front. the viaduct can actually stand more on its own being raised with minimal or no scenery. a few of these modules could be built up embankments. also works as the shinkansen lines are the most removed from other stuff in japan, its the local/express/freight that mixes in heavily with the scenery.
east penn has weekends where they set up in a large room they have access to and members just set up lots of different things from tram layouts to usually a very long setup of viaduct track just to run shinkansens on. its nice as the viaduct track does work well on its own w/o any scenery and just the trains running as compared with track directly on the tabletop. they get some pretty long setups over like 5-10 tables and usually a kato station. very fun and fast to set up and really focused you on the trains themselves! nice to see them run on longer distances on the viaduct track.
i still think you would get a lot of folks thinking out of the box if you did a set up on the fly and did scenery chunks to go into thing. im betting there are a lot of newbies and even modelers that would go hey thats something i could do w/in my resources and have fun w/o going full scale into a layout or club. our first on the fly layout drew so many folks coming in to talk about how we did it and what it took. so many saw that this was a happy medium between a layout and just a loop of track on the table. it was funny how many folks would comment they had just never thought of splitting the difference until they saw the layout. i guess its the train culture that sort of polarized this so much, but unitrak and finetrack were designed to split the difference like this for the japanese market that has to model like this most of the time.