What theme would you prefer for a mobile/online game?

I've already asked this question but I only got one answer. I have a college assignment to make a mobile size game. I need a theme for it. What kind of theme (characters and background) would you prefer when playing a game on your mobile phone? Alice in Wonderland or Harry Potter? I prefer Alice in Wonderland because I like the idea of using the cards, teapots and cups (tea party), white rabbit etc. Whereas if I use Harry Potter it will be with bludgers and the golden snitch (from the Quiddich game). Please answer. Thanks.What theme would you prefer for a mobile/online game?
If you were going to make a game i was thinking of something like all the gun killing games like mw2, mw3, cod, halo, and ect and then i was thinking of a game were god had a glitch in heaven and he was sent down to hell and had to kill all the people in hell then he went back up to heaven and then all the games in the world the person could play.