I see that you're trying to come up with a categoric formula for why TDK did so well, but - IMO at least - you can't. If you could, every film would make a billion. It's literally lightening in a bottle, and a lot of elements helped. Not saying it wasn't a very good film (it was, depsite some flaws) but the amount of external factors contributing are unctontrollable - and plenty of excellent films have made little to no money.
Things like the lack of need for humour, the inisistence on a dark ending, more villains, less villains are determined by the context - Indiana Jones for instance (the 3 good ones) had lots of campy humour and they are classics. Less CGI is always nice though.
If there are elements that set TDK apart from recent blockbusters it's the director - an intelligent approach (and little studio intervention, i hear) and, considering it's a sequel, a lack of cynicism towards the audience - i seemed like a film not a mega budget marketing event - which, at least in my opinion, is such a refreshing change
Things like the lack of need for humour, the inisistence on a dark ending, more villains, less villains are determined by the context - Indiana Jones for instance (the 3 good ones) had lots of campy humour and they are classics. Less CGI is always nice though.
If there are elements that set TDK apart from recent blockbusters it's the director - an intelligent approach (and little studio intervention, i hear) and, considering it's a sequel, a lack of cynicism towards the audience - i seemed like a film not a mega budget marketing event - which, at least in my opinion, is such a refreshing change