I would recommend a tunnel game that acts more like a urban guerrilla tunnel and less like a New York Subway Expansion. Their is nothing wrong with the tunnel map that already exists. Just imagine if the tunnel was the main attraction.

Features: Ladders, traps, smokes, claustrophobia, navigational complexity, unclear line of sights, collapsible sections of tunnels, blast doors.

Rooms: Command and Control, Supplies, Developments, Servers, Hospitals, Drone Factories.

Imagine if you could fill parts of tunnels with concrete bags to deny the usage of parts of the tunnel.
Imagine if parts of the tunnels could flood. Remember tunnels are delibertly not water tight and can't be fully flooded.

Inspirations:
https://mwi.westpoint.edu/urban-warfare-project-podcast-the-tunnels-of-gaza/
https://upload.wikimedia.org/wikipedia/commons/f/f0/VietnamCuChiTunnelstrapopen.jpg
https://tortoise-s3bucket1-1c9k2kd5zjuf0.s3.amazonaws.com/original_images/231031_SM51_gaza-tunnels_v2-1-1024x726.png.png