To be honest, putting information from multiple reports into one file sounds like a real pain. Sometime in the future, you are going to be too busy to do the combining, and you'll have files that are out of date. Having a separate sub-folder for each machine seems simplest and easiest to maintain in the long run.

You do have an option to create a spreadsheet for each machine (maybe even a tab for each machine on one spreadsheet) with hyperlinks to the individual reports. Maybe you could put a couple bits of summary information in the cells beside the hyperlink.