I think has been done before, but oh well, another chance to express my opinions.
A historical ancient china theme, as well as another non-historical theme.
LOTR is completely out, some other company already has the license.
Narnia:YES. The new series is coming out on the big screen. It's what Lego needs to sell sets, big movies that grab peoples attention. But if they did it movie-based, the figs would be skin-toned.

Oh, well.
Lego historical characters sets. Tiny boxes containing historical figures for low prices. They'd sadly be skin toned too.
Historical armies:Awesome. I can just imagine a game of Brikwars where the Romans are attacking a Celtic hill fort. Mythology:Another awesome idea. I'd love to have Poseiden fig with real trident! And trans-yellow lightning bolts for Zeus.
Generic fantasy sets. A dwarven mine, an elvish tree fort, a halfling farm, etc., plus some battles such as Trolls attack dwarves or barbarians burn farms, etc. And more coloured beards for dwarves!