The AI is often very predictable in the ships it builds to fight against you. Generally very few engines, and mostly all attack, with the possibility of a little defense thrown on if it thinks its figured out which gun you like to use most. This single minded sort of approach is very easy to overcome with just a little bit of practice at fighting ships like this.
Now, no design is going to be perfect, as there is a constant arms race going on in a given game state and both sides are trying to adjust to get an advantage.
For a long time I've wanted to be able to control the designs of ships an AI builds. This feature was added in DA... but was limited to templates, the way the ships look. This is a very nice feature I use a lot... but, I still want to be able to face AI fleets of certain compositions.
As TA has added some new combat toys to play with, I have never wanted to be able to tweak the way the AI builds ships more. It occurred to me that if the AI to handle all of the new components isn't in yet, perhaps I could ask for the algorithims I want in ship design.
First, not strictly a TA design, but a basic, balanced medium fighter as a staple of a force.

The basics of the design are simple. A single engine if needed for tactical flexibility, but nothing too large or pricey... this is optional. Then, and this is the important part, a 1/1/1 defense. Now, it doesn't have to be that low, but the first point in each catagory are the most important and hold their value no matter what design the player sends at the AI. Basically, if the AI has them, just one of the single best component for each of the three armor types, and no more. Make the rest guns and you have a tactically flexible fighter with plenty of survivability in the early 4 ship on 4 ship or less early portion of the game.
Something roughly like this:
//my rough medium fighter loadout method
if(anyShieldComponent) {add best shield component to ship}
if(anyArmorComponent) {add best armor component to ship)
if(anyChaffComponent) {add best missile defense component to ship)
while(... still space left to add weapons){
add best weapon component
}
This sort of design has been a staple for me for close to a year, and I never see the AI take advantage of mixed defenses and the huge value of that first point of defense in each category.
The next two have to do with TA only.
First, the new HP modules open a whole new kind of bully blitz that anyone with an economy can take a real advantage of... especially in lower tech speed games. Again, I just grabbed these from one of my current test games, notice the similarities:

My basic medium fighter design for my tech level in the game. And then this:

The exact same loadout but with a cargo hull and using the new +HP modules.
Now, while the speed, offense, defense and range values are all the same, there are a few differences. The cargo hull has 4 less hit points and costs 125 bc more. True, the medium fighter is the better deal. BUT - if you have the money you can build the cargo hull fighter as soon as you get your first +HP module... and these are now some of the quickest to unlock and research.
Researching medium fighters is still important from a cost perspective, but starting by slapping 4-6 of the new basic +HP modules (it works even better for Terrans and others that have the better HP components) on a cargo hull is a great boost early game, if you can afford them. Your fake medium fighters will easily slap around the tiny and small ships it runs into, and can go toe to toe with the first civs to start rolling out mediums as well. Once you start fighting medium fighters regularly you probably want to research or trade for medium fighters so you are not at a cost disadvantage.
To be clear, what I want is for the AI to be able to make these early game "cargo fighters" if it has the money for them as a stopgap measure before they have medium fighters. Right now I'm the only one using them, and I'm pushing everyone around easily on normal and slower tech rates (fast and very fast is a different animal, and these aren't quite so useful).
Third, the mothership. With the addition of the new +HP modules you can build balanced huge hull ships that can sit in against focused defense or focused offense fleets. But there's more. With the new +fleet off and def modules you want to create ships that depress their attack to hp ratio so they are targeted last. And you get something like:

Depending on my various empire bonuses I've had these babies roll off the assembly line with over 450 hp each. The design is simple, 4-6 of whatever highest level weapon you have, 25 or so of the new +HP module (preferably the +8 HP), the 1/1/1 defense I always use, +fleet def/off modules if needed, and then the rest spamming your top level defense module.
Because they have so many hit points the defense modules often get to recharge for multiple rounds... even against non-matching guns. With just a little kick and all those HPs this ship can beat a focused all offense ship in just a few rounds and still have HPs left. Against defense oriented ships these guys can win the war of bleed-through damage because they have so many more HPs. Fighting when grouped with other pure offense designs... of any size - they provide a bonus to the whole fleet and will be targeted last because they have the lowest attack per hp.
I've been using each of the above three to great effect in my games where combat actually happens. And I've been using a variation on that basic medium fighter design for forever. It seems like the AI doesn't use the new combat components though.
Could there be some way to get the AI to use one or all of these design templates? Is that outside the scope of how the current AI evaluates ship building?
Thanks,
~ Wyndstar