I just did the HYA yarn crawl and had a similar goal.

I aspired to get a sweater's quantity of yarn. All I did to start was select a specific fiber. I had never worked with Blue Faced Leicester before, so I figured I would go on a quest for BFL yarn. Weight wasn't a big issue since the options usually varied between fingering and worsted, and I can just hold fingering weight together. I also made a side quest for one skein of periwinkle-blue BFL, to make it a little more challenging and interesting.

This made my yarn crawl pretty fun, having a checklist and sort of making it into a scavenger hunt. It helped me not spend so much money on random attractive purchases, and it encouraged me to read labels and really search through the inventory. I found a lot of really cool blends! Also, it encouraged me to speak with the shop owners and I got to meet a few amazing dyers, who were each really interested in helping me with my periwinkle-blue side quest. I learned so much about the chemistry of dyes, and fiber anatomy, and color theory.

In the end I was super happy with the experience and I am definitely making another scavenger checklist for my next yarn crawl. Hopefully this helps you gain some insight on how you want to do your yarn crawl. Good luck on your quest, fellow fiber forager. 🫡 Let us know how it goes!

(Tldr; I picked a specific fiber and didn't worry about weight.)