AWESOME TO THE MAX!
Seriously I love the Mad Max movies and if they make an entire roamable "badlands" type map that would be awesome.
My thoughts: (how I think it should be)
Just think of how incredible it would be if you started off with a stock junker vehicle
Lets say that the entire environment is "randomized" in each game thus different terrain each time you play.
You can find left over buildings and claim them as your own, effectively making said building a "HOME BASE" type thing
You would have to defend your home base from attacks if it was attacked
The vehicle you start off with would be FULLY customizable
Through the "randomization" there would be left over vehicles and scrap pieces lying around from the apocalypse
You can take ANY (and I mean any) parts that you find and equip them to your current vehicle
For instance you start with a muscle car type vehicle and you come across a car that had a supercharger, you could take the entire engine or just the supercharger
or you come across some scrap metal and decide to "reinforce" select areas of your car
or you could take pieces of scrap metal and make scoops (think train like cow pusher things) or spikes for tires etc
or you come across some beefy offroad tires and you put the m on your car
The possibilities could be endless
If done with enough thought this game could be pretty badass...