Personally, I loved the Mutant Chronicles TTRPG. It's a shame nobody ever played/plays it.
Pros: Lots of setting, hardly any rules.
Cons: the rules that did exist were often pointless (deducting armor from damage in a world that has 1d6 damage vs 9 point armor with no 20-is-crit rules is pointless), so even for the existing rules you often needed to make up your own. The skill and XP system needed some fixing, as well.
Ok, I guess that's not much help, I just like making shit up as I go along, as a DM, and I like that my players do the same (instead of "gaming" the existing rules). Changing the rules, making everything arbitrary, or having my own made up secret rules all help.
The character creation was fun, too. It's like: choose background. Ok, you're born in a family of your choosing. Roll for childhood random events. Stats are modified accordingly. Choose education. Random events are rolled, stuff is modified, choose career or higher education, stuff happens, switch career, stuff happens, ok you say you're done? Right, there you go. It's not as slow as it sounds, and having the background story progress in front of you (you need to fill in blanks, for instance you can have event: "you make an enemy, you gain a nemesis" during your career, you make up the story) will make that character "come alive" a lot more, you can relate to him/her a lot better. There's also quite some tables for different careers/backgrounds, but not overwhelmingly many.