Insoles...they're different for everybody I think. My first Camino, I used what came in my boots. Not so great--but my real problems came from, first, walking in boots full of water uphill and down the day we left Roncesvalles and went to Zubiri. Which gave me blisters that were a problem for quite some time, and a purple toe because the shoes weren't quite right. (Lost that toenail eventually.) Second, when the blisters went away I got athlete's foot--which I'd never had before. (Very painful.) So I don't blame insoles for my miserable feet that year. This past year, I had the same boots, but used the Dr. Scholls Work Gel insoles and also wore Injinji liner sox. And carried the athlete's foot cream and every time there was the least bit of itching I used it liberally that evening. Wow. That was a lot better! But at the end, after probably 1200 miles or so, the shoes were dead so I tossed them. And mourned them almost daily!
This Christmas season we went to the nearest camping store (3 hour drive) and I went into the store with double sox on and came out with a lot bigger shoe--still the regular width--and while at the moment we don't know when the next Camino might be--nor the route--I'm still wearing the new boots to acclimate to them.
HTH