That's good news, it's hard to tell the extent of the polishing but generally on the piston rear skirt,slots,so on it will polish like chrome nearly.
The rear guide that is held in place via the steel through pin, if you look where the guide sits on it the pin that is you will see machining marks .
Usually I will polish that too after removing the machining rings.
If your careful and keep the plat faces as it and don't remove from the edges you could also polish the trigger sear faces.
Sometimes they require a 2000g wet n dry with oil then autosol to polish up.
Did you add a piston sleeve ,if not something like the plastic from a shampoo bottle or the old fashioned fairy liquid bottles that were.that's the kind of plastic you want almost like ptfe sheet.
On many spring air guns a sleeve is probably the cheapest or free even single best tune item.
I fit mine so as I can feel a slight contact of the spring as I slip it in .not tight but you can tell theirs a contact around the spring.
Or as close too anyway.
In my bsa rifles and scorpion pistols I found the rws hobbies in 22 totally awesome even at 100ft plus.
Nice work anyway.you can almost feel the difference when you 're fit it all after a lube.
Take it all one step at a time,you might find other metal to metal contact places that a polish may be beneficial.
I find a bronze brush through the barrel can help too.most air rifles land and grooves never ever get cleaned and some get fouled of oxidized lead and plastic even.
Won't hurt once in a lifetime.
Takes a few dozen to 're lead up to return accuracy.
Anyway your journey has started.hope you enjoyed it as much as I used too.
Well done ,I hope the action is much nicer.
Just to add ,I prefer a good spring sleeve over just a top hat .both is fine too.