Re: Getting ready to load for my wife's AR ...
Looks like you're off to a good start here, but there's one or two other itmes I'd suggest adding since you're dealing with an auto here. Number one would be a case gage, be it an RCBS Precision Mic, a Redding Instant Indicator, a Stoney Point (Hornady) or even a L.E. Wilson. Doesn't matter, just so long as you've got something to make sure that you're setting the shoulders back .003" - .004" or so. Critical stuff here in making sure the gun will run, without overly working the brass. You've got S/B F/L dies there, so you're all set in the resizing dept. Good on ya'!
You've got both 7 1/2 and 205 primers there, and I'd suggest the Remingtons are being the better choice for an AR. The 205s may be a bit more susceptable to slam fires as they do run thinner cups. Never seen one in an AR (I have in M14s/M1As) but I just really don't like tempting Murphy if I don't have to.
As for the BL-C2 powder, it'll work. I'd suggest either Benchmark or H322, as well as our N135, as being better choices for the 55 grain bullets. Don't know what twist you've got in your wife's rifle, but if you move up to heavier bullets (69s-77s, etc.) you may want to move to something a bit slower, such as our N140, N540, Varget or Reloder 15. For competitive AR shooters, these are pretty much the powders of choice for that bullet range.
Aside from that, looks like you're pretty well set here. Let us know how it does!