I took a look at arc.arc, and I didn't see any macros there that would be helped by destructuring quotation. I did notice that the macros: w/stdin, w/stdout, thread, atomic solely exist to wrap body code in a lambda (fn) expression. Maybe that sort of wrapping would be useful to add to defq?
Yes, most of the axiomatic stuff in arc.arc probably would not benefit from this I think. I can see a couple, such as "deftem", that could probably make use of this.