just keep it in the future heck im sure some (quite a bit) made it to the ark so there slums might look like edo castles but out of containers
I dunno, I feel like that's been done too much. Futuristic guns... I don't feel like there'd really be anything we haven't seen already. It may be my own creative inability to think of new sorts of guns, but that's just what I think.
As for a dystopian future where we go back to crossbows and trebuchets... that might work, if it's done more creatively, but I still feel like it's too common.
I like the ninjas fighting the samurai. I really can't even say I've seen that anywhere that I can recall. I've seen ninjas fighting ninjas, I've seen samurai fighting samurai, Americans from the same period, and demons. I don't at all expect it from Brink, so I guess I'm going off-topic, but I'll just say this: any game with the prospect of ninjas and samurai fighting (hopefully you can play both sides, but atleast let me be a sneaky ninja) would instantly draw me in.