What do you think of the idea of Darth Plageuis being around during The Phantom Menace? And do you think it is a missed opportunity to not have implemented him in the film?
I'm guessing Lucas hadn't conceived of Plageuis at the time, or Palpatine not yet being the master at the time. Retroactively establishing the latter I doubt was his idea.
But for the first question: With the film as it is, do you think that (Before it got decanonised along with all other contemporary material) enhanced the film/story or just added plot holes and unanswered questions to it?
For the second question, do you think Lucas should have conceived of him then and implement him in some way? What would you have his role be, before being murdered?