Should this kind of feature only be for ships? Or should one be able to demand other things too, such as technology perhaps?
Well, if we continue to look at Japan, the imperial army was modelled after the Preussian Army (which at the end of the 1860s was the arguable the best army in Europe). Japan will be a rather fun nation to paly. Begin with Samuraj warriors and a medieval society in 1835 and finish with top class super dreadnaughts in 1920s(!). Invading Formossa in the late 1800s, defeating China in 1895 and Russia in 1905, both on sea and on land, and occupying Siberia in 1920.
In order to pull of those military victories, Japan imported legal , educational and military systems from the western world. It also relied heavely on expanding its domestic textile industry for economic growth. It would be great to include that kind of development in Victoria.
BTW, I think battleships should be divided into Ironclads, Dreadnoughts (HMS Dreadnought), and Superdreadnoughts (HMS Warspite).