I'm a little confused about how new ships become available in the Build Ship window. In particular, I have researched Titanium Armor, and yet none of the ships available in the Build Ship window have a Defense above 0. I noticed that if I create a custom ship I can put titanium armor on it, but shouldn't there standard ships available with titanium armor on them now? Or at least the option to add it? For example, there is a FIghter available to buy, which has a Beam Weapon 1 but Defense 0, which is weird since I haven't researched Beam weapons yet.

Anyway, I just started playing and this is confusing me. If someone could explain how ships become available, that would be awesome.