Considering making baby blankets using worsted weight Lily's Sugar n' Cream for thick and 8/2 cotton. Would the difference be enough and what sett should I consider starting the sampling with? I love these blankets and it would be fun to even use Caron Cakes in acrylic for the fun multi-colors available. Not sure what thin would work for it, but washable wool-like blankets are nice for family members. Please post any combo yarns for thick & thin, I am curious which ones work best.

I've not woven with that thick yarn, except for as thick yarn (multiples) in Repp weave, so have no idea where you should start for sett. I would do a ruler wrap with your thick and thin yarns as they would be in the reed (thin thin Thick) and divide by two to get a starting point. But, as you said, sample. The same goes with acrylic. But be sure to use a thick and thin yarn with the same amount of stretch, so don't mix thin cotton weaving yarn with thick acrylic knitting yarn. That way lies disaster. Our thin linen with thick wool warp proved to be a disaster, don't repeat our mistake (and huge waste of yarn).