The software, apart from showing you waterfall plots which identify the most troublesome frequencies, will also help you position your speakers and subs.
You are preaching to the choir. What I wonder about is how to be helpful with the least amount of trouble for an audiophile, or better yet, a music-phile, who just wants to get excellent results.
I wonder how many really want to learn what the software does, measure and adjust, and also, without a lot of reading and research, come to the right answers. Having the tools doesn't mean you have the skills.
And I don't want to discourage anyone from learning. What my narrow question here is, for an audiophile who is new to the idea of room acoustics, and wants excellent results, am I doing them a service by suggesting they get a mic and REW or OmniMic, or am I better off suggesting they get a consultant like GIK to help them?