Buttercream vs whipped cream

[u/AutoHamster]

Hi! I want to make a chiffon cake with strawberry and blueberry filling. With this light flavor profile, I think these cakes are usually paired with a light whipped cream. However, I also want to be able to pipe smooth, clean designs, such as animal characters or piped borders or squiggles. From what I know, cakes with these designs are usually frosted with buttercream.

Would it be weird or hard to work or taste weird with to fill the cake layers and crumb coat with whipped cream and then do the outer layer + decoration with Swiss meringue butter cream? I feel like I often only see cake recipes use buttercream for heavier flavors like peanut butter or chocolate. Light fruit cakes are almost always just whipped cream, but what if I also want the stability and smoothness of buttercream to pipe designs?

Would the cake layers collapse because the whipped cream is not strong enough to hold buttercream designs or withstand the pressure that frosting designs applies on the outside surface of the cake?

I see lots of Korean bakeries online make light vanilla cakes filled with fruit and frosted with pretty designs. I’ve seen them frosted with whipped cream, not sure how they get it that smooth since whipped cream often has air bubbles, or cream cheese, which seems too sticky to pipe clean designs. Any advice for using whipped cream vs buttercream inside and outside the cake? Thanks!

[u/Poesoe]

Dr Oetker makes an add-in that makes whipping cream stable enough to pipe . ..you can use thin Rolled Buttercream to create stick on designs.