Springs tune up for striker fired gun

[Bench]

My next step in tuning my "cheap" gun is to do some spring work on it. It has a slide that is REALLY quite heavy but this dang thing shoots great when it decides to run the way it should. Remington mfg. says the recoil spring is 14#-16 #  but I'd like to see a bit more of the recoil go to cartridge ejection which is now about 3' or less. I've ordered a spring calibration set from Wolff and it includes striker springs also. With a touch lighter recoil spring wdo Ihich direction do I need to go with the striker spring? What are the considerations that I need to make to 'tune' this RP9 spring job with regard to these two spring sets? Thanks All.