pellet blend

Welcome to the forum.

I think there are two versions of blend.

1. The pellets themselves, some are blended and the way they are made isn't 100% of the wood specified, but a base wood with the flavor wood added, say "cherry" is 50% alder and 50% cherry

2. Mix them in the hopper to get a custom blend.

One comment you made has me confused. Haven't any idea how a wood with no salt in it can make your ribs taste saltier. New one on me. I'd suspect it's the rub or how long you put the rub on ahead of time.

If you like mesquite, go with mesquite. The key is to go with your tastes. Me personally, I don't own any mesquite and don't like the taste (I spent enough time in Texas, I'm blown out of that taste).

Smokin'

Hardwoods do contain minerals. Salt can be one of them. It's possible but not probable! But you don't know how the wood is transported (like thru ocean waterways in the NW absorbing salt along the way). Salt is a common mineral tested for in heating pellets. Salt causes corrosion in the works.