nothing wrong with frequent oil changes, just means your engine will last longer, and effectively the performance will be retained for longer.
I would say it's pointless changing the oil without changing the filter, to access the oil filter, use a deep 10mm socket to remove the fuel rail guard, get some oil filter grips to remove it, much safer than stabbing a screw driver in the side!
Make sure you replace the copper washer on the sump plug too, and ensure the car is on level ground so you can avoid over filling and damaging the engine.