Ideally we would have seen a story about the adventures of Obi-Wan, how he grew from Padawan/Knight to Master and his failure/s to teach a student aka losing him to the Dark Side ...
maybe on a sidenote we see his "sidekick" Skywalker (Anakin?) and some other guys - like the team/trio, that made the OT good and interesting ;-)
I like the "shadow" thing you suggest, Bingo - it puts "Phantom Menace" back into the story!