It's kind of like a bonus objective crate combined with a command center. You get the multiple weapons from the crate in a convenient upgradable fortification.
Each lockers upgradable level would give you access to 3 or 4 weapons; one grenade type, one precision, one power, and a general weapon.
Level 1 gets the basic/weaker weapons while level 4 gives the top tier.
If you swap out your weapon for one from the locker you would need to repair/replenish the locker after the round.
Just a thought.