It all depends on what you mean with democracy. Under the cosulate and even in the first empire, local government was much more democratic than under the ancien regime. When the Bourbon dynasty was restored, conditions became much less democratic.
In many European countries, the French presence encouraged modern reforms and the abolition of serfdom and aristocratic privileges.
So, in a very real sense, Napoleon *was* a defender of democracy. Even his imperial coronation was not simply a power-grab (that had come earlier), but an attempt to prevent a Bourbon restoration via establishment of a new dynasty.
On the other hand, a truly democratic Consul Bonaparte in a modern sense is very difficult, since it would IMO entail that he has to face regular elections and be confirmed or replaced.
So the best you can get is probably that France keeps the Consulate, the various sister republics remain republics and are not given to Bonaparte siblings and new ancientish republics are created - the Rhenish Republic in place of the GD of Berg, the Cheruskan Republic instead of the Kdm of Westphalia, the Sarmatian Republic in place of the GD of Warsaw and so on.