1. A virus hits the population? An extra-terrestrial invasion of some kind wipes out huge number of humans?
2. Tribes of wandering humans struggle to gather supplies and build some sort of base of operations.
3. Takes place in mainland North America, Britain, Australia, not sure yet.
4. No zombies, sick of those bastard zombies.
5. A new, mysterious type of technology is found by the remaining humans, they struggle to harness its power properly.
6. Different factions of humans form themselves into very unique and separate groups all over the world, wherever humans remain. Typical global conflicts, such as, between the US and China may resurface after many years.
7. I will not be watching or reading any apocalyptic fiction while I develop this idea.
8. It’s bound to be quite bad, unless I try very hard.
There we go.