Easy, go down to the gun store, sell the Ruger, by a CZ... Problem solved
. Honestly, you just need a barrel and trigger. Most of the aftermarket barrels and triggers are going to be much better than the factory ones. It's more a matter of finding a good deal on 10-22 parts right now. Anything you do find, you can easily put together yourself. Youtube has a vid of just about any 10-22 change imaginable.
As far as your ammo goes, the high velocity stuff usually gets unstable as it transitions for supersonic to subsonic. I think the subsonic stuff is what most comp shooters use. That said, I'm sure any custom barrel will shoot your Fed ammo pretty well, unless it's designed for the slow stuff.
Your scope should serve pretty well. I've got one on my CZ 452 that I like, especially for the $$.
You really might think about swapping to a CZ. They're known for out-of-the box accuracy, and for eating any ammo you feed em, and liking it. I had about $700 into my last fancy Ruger and it still didn't shoot as well as the 452. All I did to the 452 was a YoDave trigger kit. I've got less than $400 into the CZ.