I've sold bone stock Glocks and people message me after and say "What kind of aftermarket parts/springs did you put in this thing? This trigger is fantastic!!"
Disassemble the Glock, lightly polish all the wear components with some flitz metal polish, clean everything really well, and then grease the contact surfaces before reassembly.
You can sand down any high spots or plastic flashing on your trigger shoe to make it more comfortable.
That's all I do to Glock. I don't agree with changing any internal parts on a weapon that could be used for defensive purposes. On a plinking range gun, who cares. Change whatever you want.
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