Once destroyed, they are only restored upon moving to another base, and if all parking spots are used, car repairs will stop. This adds 1-5 facility spaces to various home bases. These are outside the walls, so the survivors may be more vulnerable using them. Parking spaces have been adjusted to allow additional facilities to be built. The changes are ones that I personally found to be useful or interesting. It touches upon many aspects of the game, including characters, facilities, skills, and items.
There is no central theme- it was not designed to be a 'difficulty' mod, or a 'base' mod, or a 'character' mod. Some parts are now easier some parts are now much harder. It touches upon many aspects of the game.
It is equally applicable to the player who chooses to keep a small group and rush through levels quickly, as to the player who lingers on a level as long as possible, building up the largest group of survivors they can. This mod greatly expands the variety of characters, facilities, and actions available to the player.