It sounds like the recovery plan is just what is needed. Bronze will change in color over time, just like copper pipes or pennies. Give it a good buffing out with some sorta brasso and seal it with a clear coat and it will retain the color and shine for years.
I wish my grandfather were still alive. As a Master Stone-Mason he could determine what repairs would be needed to bring the stone base back to its original state.
I imagine this is still done, and if so, a part of the visit to 8th & I could be going to the memorial and helping to square it away.
This task would be another good way to introduce prospective Marines to the history, traditions, pride, and dedication (among other things) surrounding the Marine Corps.
Who better to take care of something than those that "own" it, or will "own" it?