That was rather a long answer to a short question, but it brought up a number of thoughts about the tournament that may be useful later, so no worries.
In the main, I agree with a xenophobic approach to allowing the AI not to scout planets, and that much of a military I have no problem with -- it's a pittance that barely shows up on your maintenance screen. I will sometimes build a small fleet to protect hostile worlds that I haven't gotten around to colonizing yet, depending on the terrain I'm given. Generally, though, if I'm not planning to go to war soon and my military maintenance costs are more than 3-5% of my total income, something's wrong. (If I'm at war, I may go as high as 10-12%, and if that's not enough to make gains, it's time to sit back and wait for more of a tech lead before trying again.) That level of military is not what I'm talking about.
What I'm talking about is a full-on military assault of the biggest and baddest opponent you can find, on the largest map sizes, as early as you can manage it, with the intent not to take many worlds, but simply to raze them and kill enemy production in the womb. It seems like folly to me -- at least insofar as attacking any planets with significant missile defenses goes. You'd better have a tech advantage or at least some reasonably capable missile ships before you try anything like that. Sending in bombers at speed one or two sounds like a death sentence to me.
I've talked to one other person I consider to be very knowledgeable about MOO1, and he agrees it seems like a stupid idea, though he doesn't claim to have tried it either; he is even more defense-oriented than I am, though, and tends to wait until late in the tech tree before making his move. Either this guy on the GalCiv board is misrepresenting what he is doing, and really isn't quite so rabid on offense -- there is room for aggression without being rabid -- or else he knows something we don't. The latter seems unlikely, so I'm inclined to think he is overstating his case.
If he comes across a weak race stuck in a corner with only a few planets, it might be possible to overwhelm them even with slow ships if he has a substantial production advantage. Or, if he gains a significant amount of tech while expanding, then by the time he gets contact with all the bordering empires, he may well be at TL12-15 and in a timeframe I would normally consider starting to think about attacking. OTOH, he could just be smoking something.
I have to say that I'm quite pleased that my initial expectations about turnout look like they may be proven incorrect.