I would strongly recommend Crown of Glory: Emperor's Edition from Matrix, for this. It is a true grand strategy game, but it incorporates really challenging tactical play at the divisional, or even brigade, level. The AI is much harder at the tactical level than at the strategic level and you can play as one of several major nations from the period, with start dates at 1792, 1796, 1803, 1805, 1812, and 1815. It also incorporates a strong tactical naval game, complete with boarding, different canon shot types, wind gauge, and more. You can also write your own detailed treaties to end a conflict with another major power. It's still one of my favorite (maybe THE favorite Napoleonic game) I have. The only downside is the outdated graphics. But if you're used to John Tiller, then CoGEE won't bother you much.
Here's the link: http://www.matrixgames.com/products/366/details/Crown.of.Glory:.Emperors.Edition