Newbie co-op vs. AI... Help!

[Xentropy]

I'm fairly new to the game, and I only play one way at the moment: My friend and I co-op against the AI. Obviously at first we had no issues since the base AI is pretty much a cakewalk, so we increased the difficulty until we got a challenge.

Herein lies the problem: Using TDM AI on low bonus is a bit of a cakewalk, but on moderate bonus, we get our asses handed to us every time without even standing a chance.

Settings: Medium mid-life quadrant, two of us teamed vs. medium number of AI and neutrals, high difficulty TDM, medium bonus. 5000 point races, both of our races are designed well by everything we've read on these Boards...mine is research focused, his is religious for talismans. We start new games until we start close enough that we can meet within the first 10 turns, then tech share fully and work on separate projects, but still have a very difficult time keeping up with the AI's 3x tech. My friend usually land rushes, while I tend to fill in a little better as I expand, but in pure expansion we both exceed the AI's abilities (higher colony/system counts, usually by a somewhat wide margin). Just FYI, we play TCP/IP and are usually on the phone voice with each other as we play, so it's a true co-op.

Still, thanks to all of the AI's values being tripled, we can't keep up. Usually by turn 20-25 the AI is knocking on our doors with a fleets of 15-20 or more ships which outtech and vastly outclass our smaller fleets. Satellite defense has proven useless against TDM AI's which use proper ship designs to easily counter missile and beam sats (heavy PD from the get-go, usually). They generally have at least rudamentary minesweeping sooner than we can have mines, rendering those useless as well.

What are we doing wrong? What should we be doing? We read post after post on these forums which say the AI is a cakewalk even on the worst case settings. We read suggestions on making vs. games MORE difficult, such as using a zero point race against AI 5000 point races. And here we are on just MEDIUM bonus (not even high) and in a 2v4 or so we can't even survive past turn 30.

Any suggestions would be great. We've both read the FAQ and utilize the pertinent strategies therein, so repeating those would be less helpful. I'd love to know any of the tricks of the trade that allow all the vets here to win solo games vs. high numbers of high bonus team game TDM AI so easily they have to handicap their own racial points just for some kind of challenge. Thanks in advance!