Centerliner, first check to ensure the gap between the upper and lower end of your gas block are even: left-to-right, front-to rear. Zero expense, and if the gap is off, that could be a major cause of inaccuracy. 9/94" Allen wrench. If you have an inch-pound torque driver, about 28-30 inch-pounds. Otherwise, use your Mk-II wrist to try and keep things even. Cross-pattern tightening (just like a lug wrench on a car wheel): a little bit at a time.
Shoot it a bunch before adding anything and probably re-torque the gas block while hot just to be sure, and keep track as to the original. One mod at a time! Should you ever need to send your Mini back to Ruger, they will return it factory-stock - meaning any aftermarket mods won't come back with it; so keep any replaced parts around to restore it to factory condition before sending off.
I'm happy with the trigger-pull, with perhaps low expectations as it is a carbine and not a sniper rifle.
I feed it only quality factory ammo, mostly PPU M193 and PMC Bronze .223 REM. For my Minis, the accuracy is close enough with either to be a on-issue for my interests. Then again, my concerns are for a man-sized target out to 300 yards, standing unsupported for defensive purposes. To humanely dispatch a rabid fox or yote at 300, given the choice I'll use a 3-9X40 scope-mounted bolt gun, or allow it to get closer. Want a one-shot, one-quick-kill for innocent critters that need to be put out of their misery. Thankfully, I've never had the occasion to do either.
In short, accuracy requirements depend on your intended uses, accuracy adjustments to accommodate your requirements. Mine (and most respondents) are likely different from yours. So applying a "filter" might be prudent.