About Silo URL structure

Hello guys !

I'm currently building a new silo website with wordpress and I think I have done some nice work for the moment. I'll share my technique soon if it work well as it may help some newbie on silo.

But I have a question about URL structure and over optimisation.

I have modified category to page so my structure is actualy like that:

mywebsite.com/categoryname/postname

And my question is: It is over-optimisation if my structure is like that?

(silo keyword is "discount code" for exemple, and keyword of article is "discount code amazon")

awesomediscountcode.com/discount-code/discount-code-amazon

I'm not sure as my exact keyword in this exemple is not "discount code" but "discount code amazon".

From your experiences, should I change it to something like :

awesomediscountcode.com/discount-code/amazon ?

I think I would lost the benefitt of having the exact keyword on my URL but maybe I can avoid overoptimisation..

What's your thought on that?

Thank guys !