There is a lot of confusion about what battle fleets are decent and which ones will get your fleet destroyed and you ridiculed by friends and enemies alike. I will update this page periodically and add as often as possible. PLEASE EDIT i am a noob and would appreciate it.
The most common battle fleet is a cruiser fleet as it is cost effective. Cruiser fleets normally consist of 60% cruisers, 20% heavy cruisers, and 20% fighters/bombers.
This fleet is very effective and will work on pretty much everything in the game. However, when fighting leviathins or death stars you should have your cruisers run and leave your heavy cruisers to deal with them. Some players include battle ships and dreadnoughts for the sole purpose of destroying these capital ships. If you use this tactic you want at least 100 battleships or 25 dreadnoughts along with a consistent 15-20 thousand fighters for the meatshields. You will need fleet carriers for your fighters about 50-75 depending on your level. This tactic will let you conquer most, if not every fleet in the game. If you must use heavy cruisers to attack the large capital ships then use 5-6 hundred. that will let you defeat everything but a titan or levi stacker.
My Opinion; (Space Marine 14)
I believe the best battlefleet is (an example but scale up if you want a larger fleet). 1 Fleet Carrier, 75 frigates, 50 destroyers, 5 Battleships, 200 fighters, & 100 ion bombers. This might not be your option but this I have proven to be most effective as I have been owned by this fleet config, and then owned many other players.
First off, there is a slight error. People normally do not use Bombers/Heavy Bombers/Ion Bombers to take out anything but a Capital Ship. (Also remember that Bombers of all kinds get shot to ribbons by Fighters.)
Delta Server, James
Use Bombers and Heavy Bombers only when you want to attack a lot and Ion Bombers/Ion Frigates are for taking out Capitals.