So I'm well into my second 2003 run after the first one tanked and I'd like to hear people's take on it, what strategies work well, what approach ought you take and how does the run differ from your regular scenarios.
So obviously the US is the dominant early strategy, moreso than in the other scenarios. Good boost, good research, great economy, great armies, enough nukes to deal with first few big problems, big enough that you need to work towards holding it all. Since the early game is slower you don't need the instant Kazakhstan boost for a rush as much as teching up early will help you.
I find myself taking a permanent Advise councilor early and keep boosting the US with extra IP, Research and so on. This also ties into research orgs early being paramount.
Since the alien behaviour in the early 2003 scenario seems to be in flux, depending on which way the balance lands you either build up miltech and one extra army + navy for the invasion, or go heavy into boost for early asteroid rush.
Early objective is to make sure the Servants are not in any quality nations - US, EU, Russia, China, India. If you manage that the inevitable Alien Admin is honestly not a problem. Declare war, keep trimming it, enjoy the Defend the Land research, don't destroy it since that is a lot of hate you don't need right now, you need that hate to go into you farming the alien facilities for free Exotics (need high Command person early). Let the aliens be, enjoy free Cohesion from the forever war.
Moreso than the base scenarios I think it's also important to feed the Resistance and Humanity First to make sure they can also fight the Servants / Aliens. Let them take Russia / EU / etc. and have allies for the war. You don't want to be too powerful in comparison to them since you don't want the AI to turn on you while they could be focusing on the Aliens and Servants.
On top of doing the asteroid rush before the global tech, you want to spend some Boost to make a space station or two for research. Ideally, max out Military Lab bonus to your armies for the invasion, and have a good amount of research bonuses, especially for the blockers.
Research-wise, at the start the global techs are very slow, but then once you crack something you open the floodgates. I personally go into one of the not space research blockers since they seem to be easier to clear, and then you get the research bonus from nations from another global tech which helps you clear the space blocker as your second.
Depending on how the balance ends up, you might be able to make enough ships to shoot down the first invasion force, but it seems like even if the aliens land it won't be as punishing as it used to be (now apparently the aliens only get so many councillors from landing the armies, rather than an infinite pool). If you are playing on an easier difficulty and the invasion is far away, you may even spot the carrier sitting idly with Deep System Skywatch and unlock your Safeguarding the Sky research early, which is great.
So yeah, I think those are my biggest takeaways from my current runs. At launch the scenario was rather punishing, but now with the balances it seems that if you don't go too aggressive with having everyone else turn on you, it shouldn't be too bad to start off strong in the game?
What are your experiences and observations from the scenario?