If the fuel filter has never been replaced then it certainly should be on your list. Without proper tools it's hard to check the fuel pressure but you can carefully press in on the schrader valve on the fuel injector rail after cranking to see if gas squirts out in a good stream. Have some rags handy. Starting problems could be the camm rotation sensor starting to go bad but that wouldn't cause the idle drops that you described. Maybe the idle air control valve is going bad or there may be a relay involved in it's operation? Reseat the MAS connector and check for a split intake bellows. Dirty air filter??