Sounds great. Most games allow land units (normally ranged units) to damage naval units. Usually the ground units that are able to attack the naval units tend to do massive damage to the naval units. I've always seen the massive damage to be a flaw. Having ground units, or at least towers doing damage to naval units is fine, but when a few shots takes out an entire battleship I believe is unintentional. Here's where I see the flaw; Naval units have a base defense and health statistic normally balanced against other naval units for an appropriate battle, land units have their own health, damage, and defense statistics balanced for land battle units, what I see happening is that the units from the land are able to do massive damage to naval units because of a possible few reasons. One, the resistance or defense statistic on a naval unit doesn't exist against land ranged unit damage, the naval unit health is minimal compared to other land units so taking a few shots from little archers does a majority of the units' health.
There are a few easy ways to compensate for this mismatch such as adding high resists to non-naval based ranged damage, adding health to all naval units, etc. Just something to keep in mind when planning out the naval units.