The ejected casings hitting you in the forehead, may be an indication of a weak recoil spring. My RIA had the same problem, and replacing the spring sent the casings sailing well over my head. (My SA XD-9 exhibited the exact same problem, and I fixed that gun the same way, with a 1911 Wolf 16# spring.)
I found that the RIA weighs a few more ounces than my other 5" 1911s. It seems to help tame recoil a bit. But if you want loose that weight, I recommend using an aluminum mainspring housing, and replacing the rod in the recoil spring.
Your gun probably came with an 8rd magazine with a plastic bottom. I have a prejudice against mags with plastic bottoms, as my brain sees the plastic as the weak point. FWIW, the mag has always worked fine.
Enjoy your RIA, and don't worry about honest wear and tear on your gun. You'll own other 1911s later in life (at double the price), and you'll be thankful you learned the ropes (and possibly make some mistakes) on this one.