A fresh glassy white zaru noodles but perhaps sliced squid and jelly bonito would have been a consideration, with some wild flowers, or tangy sansho. The idea is excllent, however to eat katsubushi is sometimes difficult given it becomes fibrous, and isn’t necessarily conducive when wet.
Maybe a jelly flavoured dashi, I think these kinds of ideas are not quite inventive enough, and are work against the grain. Katsuo is best when dry, and placed a top a dish. The sensation of the dry katsuo fickles your mouth. The smoke tickles yet wet it is no doubt a second meal of stringy goo.