I wonder how r u going to add those types? I assume the Dreadnought is twice bigger than battleship and Titan will be 4 times bigger, right? Assuming the same utility and weapon slots ratio maintained, the Titan shall carry 24 large weapons and 40 large utility slots. Imagine doing 64 clicks in the designer?.. Ridicules. Unless together with new ship types u introduce a couple of extra- and super-large slot types as well. Please do not rush introducing new ships, double-think on details to not get things ugly.
Suggestion for consideration before introducing any new large ship types: rescale utility slots first, so that 1M becomes equal to 8S and 1L - to 64S (1L=8M=64S instead of 1L=2M=4S). This solves the problem with utility slots for large ships even beyond dreadnought and titan sizes. As for the weapons, new types are needed. As an alternative for doubling gun sizes u may consider doubling attack speed for those.