Suggestion:

Creature based game (like Spore) where you build a creature, evolve it, attack other creatures for resources that can be used to evolve, once you've evolved down a path of your choice you can go into colony mode where you expand your creatures colony by breeding, attack other colonies for shit, grow, defend other colonies.. If you want to start from scratch, you can nuke your colony and reclaim all of your resources so you don't start from scratch, but you start with an advantage each time.

Depending on your evolution, your breeding, attack, speed, defence, resources, etc are all effected.

For example, You could be a vicious son of a, but have no balls so you can't mate, or you could have big balls and loads of kids but be a wimp that can easily be wiped out.