My overall plan for her car is to just drain it out the pan drain plug every 15k miles (of which I've got a couple of thousand left before that happens) and then change the filter every 30k miles.
Another note of interest here is that if you have a good service writer (like an ex-shop foreman) that knows what he is doing and is confident in your abilities to perform maintenance correctly, he will make a note in your maintenance book and stamp it!!
I know when her car hit 30k miles I changed all of the fluids, filters etc. etc. and put in a new set of spark plugs. I took him the book and he stamped it.