"make it shiny'?
"leaving well enough alone" is probably best here as early Hoovers were not highly polished until later.There is a wonderful 'Tour or the Factory'booklet for dealers who might not have visited for sales rallies from early 20s that shows the entire manufacturing process.Not sure if it has been shown here.To me polishing this Hoover would be like chrome plating the oil pan on your Imperial.Might look nice but NOT correct.
Back to this Hoover, you have proved that you find them where you look for them!Where will the next back room be that has had trade ins sitting for 40 years??Very hard to find these in as original condition as yours.Bag looks great.The cloth parts should be handled with 'museum' care as you did.I think I saw an instruction book for this or very similar Hoover on EBay last week.Would be nice to display with book and attachments.As you have seen for the early part of the last century if you had rugs and carpets the best way to care for them was to go to the finest department store and ask to see'the HOOVER'.
Now when it is time to 'beat,sweep & clean' you will first have to choose which one!