A good reason why CA may not do Napoleaonic era next is the forthcoming release of Imperial Glory from Pyro, which looks very much like what would happen if you ported the RTW engine to Napoleonic times, and added in 3D sea battles.
However, if Imperial Glory is a lemon, then there will still be room for CA - but will they want to tread in someone else's footsteps, rather than lead the field?
From where I'm sitting, it looks like CA's options are limited. It is difficult to see how they can repeat the success of RTW, with an era that has equal mass market appeal and has not already been done. I think MTW 2 looks more likely as a result - at least CA already own this space, they know it in depth, and there is the existing MTW market plus new comers from RTW.
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