1) Magic is an important factor naturally. This is Eberron, after all. Have those ballistas enchanted. Magic users aren't that uncommon. Factions such as the Cloudreavers might use sea creatures against their enemies. Affecting the weather is a Lyrandar favourite, but others might try it too.
2). Alchemy is just as important. The Zil were the inventors of liquid fire(you might know it as Greek fire-funnily it is not called that in Greek) and they are still the only faction that possesses the formula. They might sell it but any attempt at reverse-engineering liquid fire has failed(pure coincidence of course).
The occasional alchemist's fire or acidic fire might be also used before boarding a ship . Last but not least, early alchemical torpedo-like weapons are rare but not unknown.
3) All sorts of fantasy stuff might appear. When there is little or low wind, warforged, undead or "monstrous"(ogres, minotaurs etc.) rowers can make a difference. Thrane, Aundair and Valenar have launched heavy, "aircraft carrier"-like ships.Thrane(the church being the originator during the Lycanthropic purge-not that it saw much use back then)mostly uses wyverns, Aundair dragonhawks(often coupled with arcane casters) and Valenar pegasi or hippogriffs(as lethal as normal Valenar cavalry). The Bloodsails love magically spreading fear and using the ghost or wraiths of dead sailors-the latter technique might be used by Karrnathi officers as well, although it is rather rare for them to do so.
Hope that helps a little
.p.s. i took the class quiz and got an avenger.
Sure the mythbusters said it couldn't work in real life, D&D isn't meant to simulate reality.
As for the signature thing, when you take the test there's text at the bottom to copy for use on a website. Below that are links to change said text for another use, the one for the forums is the "BB" option, then its just a copy and paste away from your sig.
