Fast Tracks

Laser cut wood kits for a 2' x 4' standard size portable module.
I'd think that something like this, if laser cut, would be pretty straight forward to make out of wood sheets, with interlocking tabs and gussets that will align everything for assembly, and to make it sturdy when assembled into the 3D table.
I don't know how feasible this is on your end, or even if you can handle something that big.
But I figure you have the laser cutting equipment.....
From my perspective, if somebody offered a kit like that I can:
-Combine sections myself for a home layout that could be broken down.
-Make club participation more possible.

Being an apartment dweller, and not having access to a table saw to be able to make everything sure puts a damper on my ambitions.

Before we begin, I have no personal experience with these vendors. I do not recommend, endorse or guarantee.

Level Zero
http://www.sieversbenchwork.com/
You supply either a sheet of whatever, or add risers and sub-roadbed. Or both.
Heavy, expensive, but reliable and in the business for a long time

Level one
http://www.miannebenchwork.com/default.htm
Tim - the owner and a finish carpenter - makes the frame and legs but you have to supply the plywood, OSB, or extruded foam. Not very useful for a riser approach ('open grid'), but great if you just want to throw up a sheet of 1/2 inch plywood and move past the benchwork stage. Choose your depth (24" or 30" to the wall, if I recall) and you may get the home center or lumberyard to cut the wood for you.

If it were me, I'd use two levels of insulation foam, allowing more strength AND a place to cut in for wiring or scenery, bridges, culverts -- water features as they say. Lightweight compared to Sievers if you move a lot. Don't know this vendor's current status but we corresponded in 2010.

Level two
http://tomthorpecurvedbenchwork.com/2.html
I expect these folks don't handle small jobs but I hope they would be nice enough to recommend someone for you

Level ur, um, hyperspace
http://woodlandscenics.woodlandscenics.com/show/category/ModURailSystem
This is a completely, shall we say 'original' approach. It's pricey but a few have written that it met their needs. You can choose the legs separately, the tabletop, the track pack (maybe), and a scenery kit. Not great for complex track plans. Try to find user reviews or published articles before plunging in. I'd say it's a 'love it / hate it' product