.. I was thinking about having different game modes based on the starting resources. Meaning, a long slow game for low, to a fast tough game (like it is now) for high. i may even have the game completely switched around as far as base positions and AI programming goes between the modes.
I don't want to stray from the topic too far, but how would this work? since there's selectors for each player.
Unless you just took the first player's setting or something and looked at that.
As far as making the AI harder, maybe having them put up more vehicle factories would make a lot of difference. I didn't look too hard at the AI base while I was playing, but I'm pretty sure it only had one or two VF's even near the end of the game which meant a trickle of units from their base rather than a flood.
I might have the AI watch the players in the game and constantly be trying to match the players (for example, if a player is pumping out VFs like crazy, the AI might do the same. If they're pumping out ESG tigers then the AI might pump out Thor's tigers to try and match them in a battle). The AI just has to be able to hold out against a direct attack. (Also, if the AI can't get enough ore to pump out units, you do have the advantage of it being right next to the edge of the map -- you could bring units from 'off the map' to the AI player).
Perhaps base it off of the existence of a player's spaceports, or what research they have done (ex. once they have a certain research done it is assumed they will have enough firepower to hold off the next attack).
Another twist on the game play could be where you're required to enter the AI base to get something. For example, a wreckage piece. This wreckage piece is then loaded into the Spaceport (make it prerequisite to building the phoenix module or something).
The Gene Bank is another idea here.
As for base positions switching - I do like that idea. I think it makes the mission even more replayable, which is important - after all, if you take the time to code a mission, it's a letdown after people only play it for a few weeks or months then put it away.
You don't want to make it too easy, but you don't want to make it impossible either. Changing it based on the difficulty level sounds like a good idea since that can balance it between experienced players and newbies.