Should take this elsewhere, but think.
When ships are slow, its better to be well armored and shielded. Because you can't dodge.
Therefore ships get bigger to carry heavier guns and more armor. Thus get slower.
You turn it from a game around fighters, to one around massive capital-ships, where carriers are useless.
If fighters/bombers are overpowered, then capitals die off, and its Carriers + Strikecraft.
If fighters/bombers are under-powered then they die off, and its Battleships.
Its a very very fine balance.
After WW2 Fighters/Bombers got faster and deadlier, while boats didn't get much deadlier or faster. Its why we have carrier fleets now.
With the advent of railguns, over the horizon weapons, and better anti-missile defenses, we will start to have fast assault cruisers take the primary naval role, as other ships are too slow to dodge rails, or too small to use good rails.
Speed, armor/shielding, and weapon compactness dictates combat mechanics and spread of useful ship types.
Just in case you wanted to have carriers be useful :3
I would love for this to be integrated but I can see that it would be difficult to have a constant flux between really small and really fast to really big and really strong.
Making speed require a certain resource would allow a flux between factions. Would be cool to see the interplay between factions with large amounts of the resource and factions without.
Research is another option to include it, but I expect it would lead to one type being good for a small amount if time, and the other dominating the rest of the game.
Could implement a sinusoidal system where every "basic" technology can be improved up to a point, and if you keep trying to improve that technology, you can have a eureka tech, where you get a new tech to improve upon that's equivalent to the max of the previous tier. Would have to worry about power creep though...
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