I've been doing this model of a kunai for practice, and i wonder if i correctly created it. This object has no use, but if you really want to think about the purpose of it cosider it a videogame prop.
there are some edge loops that it looks like if you deleted them, the silhouette won't change. I'd consider that a small inefficiency, but in big scheme of things it probably won't amount to much. Don't hurt to be efficient just on principle though if the time cost isn't too much. Long thin triangles can sometimes cause…
do they all really need to be as 1 piece, like a highly maufactured piece?. I would preosnally spilt them in to subobjects and maybe even just use bevels wihoout subd ( maybe jsut 1) and use a normal map just for surface detail you can achieve a lot with bevels and weighted normals these days…