Not sure I follow the relationship between a recoil spring and a striker spring. The striker spring doesn't assist in bringing the gun into battery - that's all in the recoil spring.
The only thing you might get with a lightened striker spring is light strikes on the primer - FTF's. Not failure to go into battery.
What Braxton1 said was correct, the striker acts in the opposing direction of the recoil spring in a Glock. Don't know about other plastic guns.
So if you lighten the striker spring, wouldn't that make the gun go into battery more easily?