Customization opens a whole 'can of worms' as I see it. Sure, it would be great to play with sail area, hull designs, cannon numbers and types plus crew training, naming of vessels (a chrome idea), etc. Players will want this so that they aren't confined to just 'historical' vessels. However, most ship types and/or classes that this game will eventually incorporate will be based on historical precendents simply because, through 'historical trial and error' only certain design parameters worked and/or were found to be cost effective. So, let us have our cake (historical vessels and battles) and eat it too (player built fantasy vessels)!
Regardless, I want to play a 73+ (all the vessels inc the single deckers) player re-enactment of the Battle of Trafalgar for one and, secondly, a way to play my very own game built single, double, triple & even a four decker (a la the Santa Navidad). BTW - I have the out of print 'Trafalgar Board Game (only four ships aside & very simple but what great fun it is/was deciding on whether to fire at masts/sails or guns.