To begin with, do you know why morale is low?
Is there a driving factor that's causing / triggering
the drop in staff satisfaction?
The idea of offering incentives is all well and good, but,
doesn't tackle the underlying issues and problems. It's more
of a Band-Aid on the situation. You're going to have to dig
a bit deeper and start looking at doing a root cause analysis.
As a starter try pulling together a few focus groups from
within the agent community, give them opportunity to talk
stressing that it is totally confidential, and, that their
free and frank views are required regardless of how painful
it may be to you. :-)
This should then give you the insight to start addressing
those issues YOU CAN. Obviously you are not going to be able
to guarantee Smoked Salmon and Caviar on the menu once a week
but, can probably get some quick wins.
Hope it helps as a starter.
Good luck, do please let us know how you get on...