Thanks for the replies
I ran the replay and it was a combination of two things. 1) The computer had a lot of Weapon Platforms and 2) there were 118 satellites which had PD cannons... my fighters were too stupid on Strategic to take out the sats first so they kept charging ahead and getting mowed down as they tried to reach the planet.
I still plan to play Strategic since one battle with that many fighters would take hours... but I will definitely take the suggestion about mixing my fighter types.
Thanks!
Jason2