Update BLU.
Make him do PotD/HoH. (With deactivated solo achievement)
Make him do Ultimates (with deactivated reward's and "clear" status) no matter if he is able to clear them or not.
Eureka/Bozja (with limited use of area specific action's) probably not needed for Eureka/BA but BLU flare star would be to strong.

These are easy to implement things and would give BLU so much more content.
Maybe add hidden achievements for the case that a full Blu group somehow kills a ultimate.