Should mention, there are companies that you can send you trigger in to get it "improved" . This is one area of improvement, I feel is worth the cost, as it increases ones ability to shoot more accurately . Strange, that even Ruger makes an improved, drop-in trigger for the 10-22. Not sure of cost, some trigger improvements can be costly,so let your budget be your guide.
If you don't feel like dropping $200 to $350 for an entirely new trigger, you can buy trigger kits for around 50 bucks from VQ. KIDD, TK, etc. that will really improve the factory trigger.
As mentioned, the Ruger BK trigger group is a good choice for under $75.00, But still not as good as a KIDD. In fact. KIDD makes THE BEST 10-22 trigger on the planet (as well as bolts. barrels, receivers, etc.). Single Stage or 2 Stage. Well worth the money for anyone serious about squeezing every bit of accuracy out of their 10-22.
If I had all the money back that I spent using other parts (GM barrels, Fedderson barrels, VQ Barrels, VQ TG2000 trigger, Timney trigger, BK Trigger, BC stocks, Houge stocks, Core-lite stocks, Victor stocks, and God knows what all else, I could have built a half dozen KIDD 10-22 rifles!
Once you build a rifle with decent quality parts, then comes the search for ammo that your particular rifle likes best.
Good luck and just have fun doing it!