So, I just won an ultra hard game as the AM against the AI (coincidentally against the AM again) on a very small map and I noticed a few things. First of all, the beginning turns are the most important and you have to know what you are doing because you will get cock blocked by resource shortages very fast. At one point, you can go for 10s of turns without being able to train a unit because everything is so expensive and the resource buildings give so little income. This kind of creates this dynamic where you are front-loading your unit production in the early game. This is exacerbated by the fact you basically need all the level 1 and 2 research. You NEED grenades, you NEED tanks (chimeras, I'll get into it), you NEED heroes*, you NEED techpriests, you NEED heavy weapon squads. Which is good on paper, nothing goes to waste. However, there are two problems - the AM early game is kinda always the same because you have to get all this research, which feeds into the second problem. Which is that the AM are very weak without all of this research, I haven't noticed the other factions being this powerless at the start. Soldiers die like flies, but aren't very easy to replace, especially once you hit that resource cock block after a few dozen turns, but also because they take 4 turns to create (on the normal speed). Which means you also NEED the barracks production ordinance research. Or at least it seems so at first glance. What you actually have to be doing is not letting anyone die, but that is impossible without the aforementioned chimeras. Chimeras have 2 problems, they fill in every possible weakness of the AM: squishy units, low damage, lack of movement speed. Which means they are absolutely essential and you can not win or make any progress on the higher difficulties without employing them liberally.
That makes the AM's early playstyle severely reliant on chimeras. Not only that, which is a sin in itself imo, but it also reveals the second problem. They are DLC. I know the DLC is like 2 euro when it's discounted and they discount them all the time, but it still leaves a bad taste in my mouth. It's pay-to-win with the AM and that's a perversion. It's the Sisters of Avelorn problem in TW Warhammer 2 all over again, but at least the high elves can win without them even on the highest difficulties. Maybe you can win with the AM too and that's only really a problem on a very small map against the AI, but that's what it boils down to on these settings. The AM are so weak that I'm not sure you can win when it isn't a mirror match. Tomorrow, I'm going to try to win against something else on the same settings, but I kinda feel it's a lost cause. Also, I now have all the faction DLC apart from the T'au (yeah, the worst race in the entire WH40k roster, I'd have preferred literally anyone else), but the random AI seems to always pick one of the 4 original factions to play as, kinda weird.
*You don't actually need heroes, but the tank commander is quite a beefy unit. I won this game only with a single Lord Commissar because I was so resource starved I couldn't get out a second hero.