Unfortunately, due to the way I handle units occupying hexes, the bridges are permanent. Only one combat-enabled or targetable entity can occupy a hex, meaning that I had to implement bridges as actual changes to the structure of the environment. I am thinking about revamping it so that I can make bridges destructible as a tactical option. That would require a fairly significant change to the underpinnings of the hex map, though, requiring me to enable more than one combat-enabled unit per hex. This could get hairy, given the fact that so many other systems (spell targeting, etc...) would be affected.
I've begun the long, and long-overdue, re-design of the level generation system. The way I have begun to envision the gameplay is that you proceed through a set of missions, joinable from the mission map. At any given time there will usually be a fair variety of missions available, and they come in various shapes and sizes. One mission might be an exploration mission, with a relatively large map and certain objectives that must be found to complete. Another might be to clear a beast den; this would be a fairly small map with thematic monster placement and a final "den alpha" end boss. Another might be a treasure mission, with a tiny map and a treasure to loot. Ideally, I would like a variety of mission sizes and lengths, in order to accommodate various playtimes. If you only have a few minutes, you might want to do a small exploration or boss-fight map. If you have hours, a big, meaty dungeon-delve might be the way to go. Rewards, of course, would be proportionate to the size of the mission.
Toward that end, I've ripped out all the hard-coded level generation and have begun to design the modular system for generating a map based on location, theme, size, environment, and type. I still don't have the mission map system finished, though, so selecting new missions is still only possible via the console, and there is none of the coherence between successive maps that I (hopefully) will have once it is complete.