Haha, thanks!
(if you were to implemente some of them, you could still offer me an android version when released ;-p)
Famine:
The city is filled with famished urchins. Famished urchins (neutral) pop up in the city and can move a few tiles every turn. Famished urchins can group in the same way as gangs. They don't block the path, can't be killed, but you can block them with a thug or a gang. You can also send a gang or master truant at them. It allows you to move them a few tiles away (if it is a group, the number you move depends on "evicts" level)
If they enter a building, they block it untill evicted and they evict player's urchins. If they enter the head quarter, they steal money and/or lanterns, then disappear.
Urchins evicted from a building (famished and player's ) go back in the street (famished).
The only way to gey rid of them is to buy them by sending the master thief (same cost rule as regular urchins). Sending a master thief at a group of famished urchins tries to purchase as many as money allows.To destroy urchins (as their number will keep growing), you can play those you have purchased on your headquarter.
So this map would not offer new opportunities, but is rather a race agaisnt a growing threat you can throw at each other.