I've got about 71k on my 08' I change my cabin air filter about every 2 years @ about 10.00 per filter. Engine air filter you should change it if its still original. I put a K & N drop-in in mine, but there is heated debate about that on the internet. But deffinately change it if its never been changed. I'm planning on doing spark plugs around 80k which requires removal of the intake manifold & new manifold gaskets.... while in there i'm gonna see how well the spark plug wires are holding up. I can't comment on which plugs to use, since I haven't looked into that yet. I also pour a can of Seafoam into the gas tank about every 5,000 - 7500 miles. This is for all the junk they put in gas these days - chemicals/additives/ethanol. The Seafoam cleans up the combustion chamber and alleviates ticking/pinging and improves fuel economy slightly. You can find Seafoam at Walmart or Auto Parts Stores, its between 5 and 10 dollars a can, use a full can in about 3/4 tank of gas and run until you are nearly out of gas. I also rotate in a tank of 89 octane from a quality gas station such as exxon/mobil and make sure the pump doesn't have the "contains up to 10% ethanol." Other nit picky options - I took my hitch off since its just dead weight, store it in the shed. I also am very OCD about frequent 4 wheel alignments and roadforce balancing of all 4 wheels/tires. Out of line & improperly balanced wheels will reduce fuel economy, just slightly.
Hope that helps!