And what do you mean with the unit placement thing? Could you specify where you would put your units as the AI? And what do you have against overpowered units? Do you rather like to see weaker units? About the geothermal plants: To get more energy.
Try to put the player's starting vehicles in some kind of interesting layout or pattern. Spread them out, especially from the other players (even if they are supposed to be allies; you should be close to the other players but not that close).
As for the AI, I guess my complaint is why are there convoys of attack units dedicated to patrolling the open desert? It really only makes sense as some kind of difficulty barrier to prevent the players from moving too far too early. But from a realistic standpoint, it doesn't make sense. No human would decide to have their precious combat units defend open terrain. It'd be a waste. Not to mention patrolling units have a tendency to get separated from each other, making them easy to pick off (especially if the other units in their convoy don't rush to help them).
About the overpowered units, it's not that I mind a good challenge. But look at Caught in the Crossfire. The AI starts with Tigers equipped with powerful weapons. But they're all on permanent guard duty. If you want the AI to start with Thor's Hammer, then keep them inside the base. There's no need to throw them at a player that doesn't even have a Laser Guard Post.
And yes, I know Geothermal Power Plants produce lots of power. But why are they there, so far from the AI's base? There are four of them; that's a pretty tempting target for anyone who knows what they're doing, and they're lightly defended if I remember correctly. I'm guessing this was done so players could weaken the AI before assaulting their main base, but it just seems jarring for some reason.
Oh, and about the random beacons, "if you don't like it restart" doesn't cut it. You need to code some kind of "safety net" to ensure there's at least one common ore mine per player in the lower (safer) part of the map.
And while you're at it, make the Blight faster. I don't think it even got to our start "base" before we were done.