That is an interesting table layout.
I've been wanting to do something similar, for recon/scouting games, and was thinking about having a three-pronged avenue of approach set-up, with not enough forces to properly defend.
The defender would need to predeploy assets in advance, but might get reinforcements, or backup from the other areas, depending upon how things develop.
The attacker(s) would need to perform recon work, to determine the best avenue to assault – least defended route. The other avenues would need to provide a screening force to block any reinforcements, or counterattacks from the other routes not chosen.
Depending upon the size of the minis chosen, and game scale, I think you could do 2 – 3 parallel routes across the width of a 6' table, using 20" per km. as a game scale. Mountains, hills, forests, rivers/streams, and villages/towns could be used to keep the routes somewhat separate from one another.
Another idea is to have a single or double line of approach, using individual 6' wide tables, with a lot of length to them, and then branching off to the sides at a major crossroads, into a multi-pronged table arrangement, kind of like a trident. The handle is the main approach avenue, and the three prongs are the possible routes of attack that can be chosen.
You'd need lots of terrain, groundcover, and tables to do that, but I suspect it could be very interesting.
There'd be plenty of walking access between the prongs to permit people to get to the different routes and miniatures on them.
As the forces advance, they need to also maintain control of the crossroads, to defend against possible counterattacks.