Going to attempt something like this design...would you  use royal icing or buttercream? (on a buttercream cake). Those ruffles almost look like fondant...

Wafer paper for the ruffles? Royal icing or sugar veil for the rest. Woof that's a gorgeous cake.

You could use fondant, as it looks like the wide stripe next to the ruffles might be fondant.

Isn't it lovely? Hope i can come sort of close . hmmm was hoping to not use fondant

you could also use candy clay (modeling chocolate) or gum paste.   or you could use royal icing for the wide parts.  I wouldn't personally use royal for the ruffles as I would be paranoid about breaking.

I think it's gumpaste for the ruffles and royal icing piped on for the rest of it. Makes my hand hurt looking at it...   :/

costumeczar the more I look at it the more I think you are exactly right. Yes, luckily my cake is half the size

"Makes my hand hurt looking at it...   :/"

Hahaha exactly my thoughts.

I would also make sure that you get the piped lines all parallel.  Looking at the cake (which is gorgeous! ) I can't help but stare at the lines in the right mirrored C. They go in the wrong direction. And also the piping on the second layer I'd a bit off. Maybe that's just me being OCD,  but I noticed that straight away and for me it brakes with the otherwise quite clean and symmetric pattern.