Well, it will be a major leap in strategy game AI if the description is accurate. Feints by the AI? I'd love it! I'll believe it when I see it. But what the heck are they talking about here?:

Flotillas must be varied and made of fast and small as well as big and large ships, just as an army needs varied troops on the ground.
That's not how classic battles were fought in the days of sailing ships. It sounds like they're trying to mimic cavalry flanking tactics from land battles or something. You cannot fight like that at sea, due to very restricted sailing angles caused by the wind direction. Unless they're allowing "sailing" directly into the wind (please, please, don't do this).

If a fleet was mixed between large and small ships, it was only due to limitations of logistics or economics. It wasn't an intentional mix for tactical purposes. That's just nuts. Every admiral would much rather have ships of the line in battle. It may not be as "fun" as mimicing land battles with flanking and skirmishing by smaller/faster ships, but the fact is that battles were won by big warships with the heaviest firepower (not to mention capacity for the largest complement of marines in case of boarding).

From Wiki (http://en.wikipedia.org/wiki/Ship_of_the_line):

A ship-of-the-line was a type of naval warship constructed from the 17th century through the mid-19th century, to take part in the the naval tactic known as the line of battle, in which two columns of opposing warships would manoeuvre to bring the greatest weight of broadside guns to bear. Since these engagements were almost invariably won by the heaviest ships carrying the most powerful guns, the natural progression was to build sailing vessels that were the largest and most powerful of their time.
So, what is the CA dev team (or their marketing department) talking about here? Will naval combat in Empire be an arcade game? Or will it be at least semi-historical like the land combat?