I'm not a big fan of this concept at all, it would require lots of dev-time that would be spent better elsewhere, just to mitigate a destroyed bell that would be the result of bad planning / inactivity / treason / ... which would be like making those mistakes less bad, I doubt that is intended.
Though, if it would be intended, I'd say to prevent any abuse it would be best to do it like this:
- destroying a town bell spawns a "destroyed townbell object" in its exact place
- town members stay members, but all rights and town effects except for the town chat are inactive if a "destroyed townbell" is there
- a "destroyed townbell" can be repaired (costly), replacing itself with a regular townbell if done, and restoring the town as it was (with all previously connected authority objects)
- a "destroyed townbell" is indestructable as long as there is authority left in the former towns pool
- a "destroyed townbell" takes the current drain right before the regular townbells destruction, and continues to drain the remaining authority at that rate
- would turn a poopclaim into an important tool for completely destroying a town
I guess that would be a possible implementation with no relevant side effects or exploits, yet, as I said, the idea to be able to "revive" a destroyed town would mean certain mistakes are less severe, and therefore likely not intended.