Although I've currently put this and my other collections on a temporary hiatus, I still wanted to put this idea out there, since I already hadn't updated here for awhile even before the hiatus.
I want Chaldea, as well as the cast of Fate/stay night and Fate/zero, to react to Archer's identity, life, and capabilities. I'm not exactly sure how I want this to go, so I'm going to leave a lot of room for freedom of writing on this idea.
I'm particularly interested to see their reaction to his identity, so please give the proper attention to however the reveal of that will go down. You can use scenes from UBW to help explain how he is better, if you'd like, just as you can also use scenes from HF or Fate to display certain aspects of his character and/or his fighting capabilities.
UBW would be used to show the majority of how he is, but HF could show that he can still be heroic at times, and Fate could show just how powerful he is, being able to take so many of Berserker's lives and all. Just include Archer scenes from the three routes, however, not the routes in their entireties. At most, give a brief summary of the events that are occur in each route, and what Archer is doing in each of the scenes you show.