Confused on crucible skill tree

Do unique weapons have unique crucible skill tree with powerful nodes while rare weapons don’t? And to activate the skill tree for unique weapons you need to sacrifice one copy?

You can't combine unique weapons with rare weapons, if that is what you mean. A unique weapon can only be combined with the same unique weapon.

I think chancing white weapons with good crucible trees will be a thing this league.

Activating the skill tree of a unique weapon requires a particular mod on the map items you can get.

Unique items don't have special access to the powerful passives, from the sounds of things. Those passives will probably be limited to ilvl 84+ items though though.

I see. So I guess we have to try various weapons to find the one that best fit. Thanks