[Taqwus]

When playing as a Ruthless Back-stabbin' Warrior Technologist, I tend to

a) strike first, and
b) use ships with range advantages due to solar cells

If you can fight enemies entirely in their space, because they can't reach yours and have any supply left, then you need very few ships -- I've won with 70 warships in a 255-system galaxy, especially in a Cluster system. This might not be as feasible now, because the ModPack AIs have improved AI ship design... but even still, I rarely put more than 20 ships in a single fleet.

(* Note -- you can get away with having fewer ships if you have a very large intelligence network. If you have enough points, you can subvert 10-12 ships instantly... quite useful for a quick defense. *)

At the other ridiculous end of the scale, in my "Mr. Nice Superpower" game (no Mega-Evil... but also, trying to avoid wars without an excuse, such as persistent attacks on an ally, or incursions into my space, and then preferably short wars that DON'T result in a surrender), I've got over 800 ships (many, if not most, *not* warships -- think colony ships, warp ships, repair, shipyard, scanner, minesweeper, plague/medical, troop transports, planet makers, etc) to go along with maybe 890 worlds. It's slow trying to convince AIs to make peace with each other, without simply demanding their surrender and instantly absorbing them.

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-- The thing that goes bump in the night