Formations for HUGE battles ?

[LGM]

Your opponent should have the same problems. If your opponents fleets are no where near that size, you are over concentrated and should attack more directions simultaneously.

With Large formations, you want to break formation to let ships move to their own desired ranges. Largest I have deployed has been around 150. Only with a Missle fleets would I recommend going above that number. Missles are not hindered by ship/unit congestion.

A formation like Decoy Arrow will leave some diagonal gaps for movement. I am not sure what it will do when it runs out of places. In the past (pre gold), everything was lumped behind the formation that did not fit.