At Least Some Replay Value
First, if you can, I think it's a good idea to get a copy of each of the three volumes of L'Aigle. Also, don't forget to download the free 1815 Waterloo campaign from the Pratzen Editions site. All that will give you all the major campaigns of the Napoleonic Wars. That said, it is possible in at least some scenarios to vary the initial deployments so that alone will give you some variation and with it replay value.