Hey, so I just tested your vanilla design against an older broadsider based dreadnought of mine, and noticed some things. I used the A.I., but manually guided (or tried to, I'll get to that in a moment) your suicide ships.
Dreadnought design in question:
First off, I found the suicide ships to be too ineffectual to warrant their use. They were fast, but not very maneuverable, and I spent the a great deal of the early portion of the battle trying to guide them into my ship. I only managed to get one close enough (the others were blown up by mine as they circled around it), and it did very little damage. I love little fighters and carriers in general, but I'd recommend making these ones armed with actual weapons instead, along with giving them more directional thrusters.
I also found that your ship's weapon batteries were prone to exploding violently, most likley due to reactor clumping. Also keep in mind that factories will also explode. I think more shielding would be of some help, ESPECIALLY around the frontal railguns, which went down very quickly (I think they got one, maybe two shots off?). Also, I'm not sure what the 4 cannons inside the ship are for. Perhaps it's something obvious and I just missed it?
Finally, focusing your firepower in less directions, or it least in a more dense layout, might be good. Your current weapons are very spread out across three sides, making it good against multiple ships, but unable to deal the most amount of damage against one or two ships.
It is a cool design, though. Like the paint, and like I said, I love carriers. It gives me a Star Wars Venator vibe - a battleship-carrier hybrid. Good luck!
EDIT: Upon looking at your ship closer, I noticed some other things that you might want to know about. The main problem was compartmentalization (which, if you look at any of the designs I've posted, I am not great at compartmentalization). Still, I noticed that along the edges of the ship, your compartmentalization was pretty good. You could definitely get away with improving it by removing some doors, but its alright. The main issue is the area right behind the suicide ships. That is one, massive compartment, and worse yet, it links with the two batteries on the outside, creating an even larger compartment. This vastly decreases crew efficiency, and the overall combat performance of your ship. I would also get rid of, or at least move a lot of the ammo and missile storage units. I find just having factories is generally better, and a lot of your storage units are very far away, making them not helpful to begin with.