My biggest fleet right now consists of 10 athena, 15 posi, 15 apollo, 20 arti, 12 herc, 10 atlas and 8 dio. The fighters are used simply for cannon fodder. They're cheap and they take hits so your larger ships take less damage. I mostly use my atlas for raiding inactives due to their weak stats, but their speed gets them home sooner so I can send them back out. The hercs are good for raiding people with fleets/defenses because they can take a couple shots before they go down. Posidons are a pretty standard staple of most good fleets. They rapid fire against the beginning ship and defense so they're good for taking out the enemies fodder quickly. Athenas are the real backbone of any good fleet. While they don't have rapid fire against anything of value, they're very cost efficient and have fairly good stats. Most people won't use the Ares because they're only effective against defenses and they're damn slow. Hades are very good because they rapid fire against everything that's below them, but their a little more expensive in the crystal department. As for the other ships, I haven't had any experience with them. The Prom and Zeus are very slow but very powerful. I did a battlecalc sim against 1 Zeus and they are very hard to destroy. I would use them as a defensive weapon more than offensive due to their speed.