I would say shoot the darn thing before making changes! You may like it the way it comes from Glock.
Which generation 22? I'm happy with my older one and the only upgrade is night sights. If buying new, I'd skip the Gen 3 and get the 4.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together. You'll remember the quality of a gun long after you forget how much you paid for it.
US Army 1966-69, VFW Life Member, Retired Geek