There is no need to pick up any items in the game at all. The devs have removed any use from rares. Blues and whites were always used for mats outside of the first few weeks of launch.
If you're running low on mats, spend 2-3 hours running Normal games @ Battlefields A5 map. Open all the armor piles and loot something like 2000+ white mats per hour. Take them to cube, transfer them to yellow/blue. You could probably get 7500+ yellow and 7500+ blue mats in one night of grinding and never have to pick up another item for 1-2 months of rerolling shit.