Not one mention of "Musings"? Even if you realize it's not good for the plot line even as exgeratation (CSM fixing the Olympics, really?), it does give flavor to the character that really was the best of the show.
As far as acting in an episode goes, I'd say "Biogenesis", mainly because of the CSM/Mulder dream sequences. "Two fathers/One Son" was probably the best, or in a tie with "Anasazi/Blessing Way/Paperclip".
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Our first challenge is to create an entire economic infrastructure, from top to bottom, out of whole cloth.
-CEO Nwabudike Morgan, "The Centauri Monopoly"
Sid Meier's Alpha Centauri (Firaxis Games)