There are no special secrets to keeping the 9500 going trouble free except to use it as often as you can, this printer can also sit for weeks without the heads clogging up, but the best way to help the machine stay happy and trouble free is to run the Ink Quality Maintenance at start-up followed by a nozzle check.
Printing small amounts of photos is a bad thing, wait till you have accumulated a dozen or so and that will save you a lot of unnecessary waste ink..