I forgot to mention that this is strictly a flavor combination experiment, not someone's wedding cake.
Sounds like berry is the way to fill this project. I was thinking of a wild strawberry filling. I have wild strawberries growing profusely along the fenceline of my yard. Anyway, I plan on picking them and using them as my filling.
I wonder, if I threw some orange marmalade in between, instead of a berry filling, would it remind someone of a mimosa?
I use smbc, which is not very sweet. Which type of buttercream did you try it with, mom2twogrlz?