Intro..New .25 cricket onwer

As said in the subject, recieved my new cricket last week. Very impressed so far with the gun but i havnt had a chance to really test her out due to the snow and sub arctic temps here in mass. Ive done some shooting out the back door at an existing target about 40yds away, but am not relying on the groups due to gusts of wind.
It seems the avg. is about half in. at 40yds, which is good in my book. As far as pellets, ive tried all the .25 pellets i had and they all seem to shine at that distance.
From the groups i shot, the benji domes seem to outshine the jsb’s by a lil bit. Again, this could be due to added weight of the pellet and the wind not having as much an effect on them. Overall, im very pleased with gun and especially shot count. Not sure where the reg. is set to but i fill to 220 and after 4 full mags the pressure reads 140ish!!

So now my question to the seasoned cricket owners. I understand ernest is the guy to go to for a tune, but im strapped for cash right now. Id like to hear what differences people noticed pre and post tune if possible.. Also, i did not clean barrel before shooting her and im thinking that when i have it off, i might as well polish the barrel. Im nervous about fiddling with it so if anyone has experience with this id love to hear how you did it. Ive already done the search here and at gta but it seems everyone has different views on what to use and how to go about it. Ive heard about diamond paste for polishing but again, i have no experience with it. Im by no means a gunsmith but i do love to tinker so if anyone has tips id greatly appreciate it.. Or should i just leave her be lol