Howdy consider using acoustic caulk at the rim joist to the foundation it expands and contracts with temp changes and works great. The fiberglass does not restrict air flow- its first a filter secondly an insulator. Might add 2" of pink foam board into the ends of the joist bays and caulk or spray foam , use thee cans a little bead goes along way, The 4 by 8' sheets of foam board are easy to cut an install and a high R value per sw inch. Advantage is reducing the heat sink at the rim and the foam does not allow air movement.