Vapor1, I am intrigued by this idea. Can the 4uF cap really have that much influence even though it is only roughly 16% of the total capacitance?
Yes, with some caveats. The Clarity ESA and MR are very similar in character, so this approach works well. If for instance you put a 4uf MR on top of a 20uf oil/paper cap, the results would be more unpredictable. I have used combination of Clarity ESA and Jensen copper foil/oil caps for the smaller value and it worked well, the Jensen character is most prevalent in that case.
For large values like this my go-to is ESA for the big part and whatever flavor on top of them. Since the ESA's are very neutral it's proven to be a solid approach.
Pretty much whatever you do though is going to be better than the Bennic electrolytics.