hmm, just off the top of my head
lets see for 1500 pts
IN: 3 dictators, 3 lunars with NC, 50 pts admiral, firestorms and falchions
CN: 2 devastations, 2 carnages, 3 slaughters, 100 pts admiral, and repulsive
SM: 2 battlebarges, 50 pts admiral, 3 strike cruisers, and novas
Necron: 1 tomb ship, 3 scythes
(the IN and CN are my standard fleet)
not saying these fleet will always beat 3 explorers & 2 heroes
but the game should be fun and the fleets competitive
tactics:
1. close to the explorers and take them out with direct fire.
2. use ordnance to take out orcas first, then heroes. i wouldn't bother with CAPs, or fighters but always launch bombers and see if the tau player would divert from launching mantas to launch fighters instead