And I think that's what the original trilogy did (ESB in particular)--it was a little more serious and mature, and wasn't dumbed down. But it still kept that sense of adventure and urgency of having to defeat "the bad guy". It presented a basically simple good vs evil plot, but layering it with complex relationships and slightly complicated characters, so the viewer could grow to appreciate those things as they aged.
I think all 4 of those directors are more than capable of achieving that. In their movies, they have been able to provide great thrills and fun, and instill the characters with enough personality that the audience truly cares what happens to them.