The drengin had 5 frigates. I went searching all the boxes in the tech tree with no clue what I needed to also build a frigate. There should be a legend, with pictures of each ship that can eventually be built and it should tell you 'exactly what you need to make that ship' and if you have some of the techs already, it should tell you ONLY what you still need to make it.
The AI doesn't use set design molds. Thier ships are designed based upon what tech they ave, and are given names accordingly.
I had researched weapons all the way to Warp drive
Warp drive isn't a weapon, it is an enigne. I"m guessing you just got confused, so it's not a big deal.
And what's the deal with defense? I spent a lot of time researching up to 4 defense against missles. Didn't really make any difference on ships that had it. Seems like def is really useless now. I probably lost that game due to the amount of time wasted researching up the def tree.
During the early game I don't use defenses much, but by end game they can make your ships almost invincible.
As the others have mentioned, you really want to be building your own ships. Since the AI will react to your military by designing ships specifically to counter yours, you will want to do the same.
As with anything, since this isn't a game based upon twitch speed and reflexes, you'll get better with practice. It ust takes a little time, with a good dose of trial and error.