Ship size issues

[heroquestelf]

I have two questions:

First: when I'm in game, I only minister that I use is the ship design minister. One of my main strategies is that I push my tech envelope as hard as I can, and keeping up with ship modifications every time I get a new tech is bothersome, so I let my ministers do it. The only issue is that my ministers won't build dreadnoughts. The biggest thing they will build is battleships. How do I modify this?

Secondly, and this is a branch off from the first, I found a ship-size mod that adds several new ship sizes and makes the dreadnought truly a massive ship. If I use this mod, my concern is that the AI's won't use the larger ships and I'll have an unfair advantage. How do I make sure that the AI's research and use the larger ships as well?