Last night I played my second 2 player game of Terraforming Mars against Naked Man. I won, and it was an absolute rout - the score was 104 to 64, partly on the back of me getting 3 milestones and the first 2 awards, leaving only the last and most expensive award for Naked Man to collect. We both felt throughout the game that I was ahead but I honestly had no concept of just how big the lead was until the final score landed.
We were both musing on how exactly I won by so much. There were two things that really stood out, one of which was Naked Man focusing too hard on a single strategy, the other of which was just me getting a ton of punish cards. Naked Man went for a heavy space strategy, starting with titanium income from his corporation and adding on a ton of additional titanium income throughout the game. He ended up at 6 titanium per turn, and that is way too much. Most of the time you can just count titanium as being worth 3 bucks each, and as long as you find enough space cards to spend it on that is accurate. Unfortunately for him we got fewer space cards than we rated to and so he had 30 titanium sitting in front of him by game end. It was pretending to be worth 90 bucks but nobody was buying the act.
This is an important lesson. There isn't really much of a 'space/titanium strategy' exactly. If you go all in on titanium you will likely end up with far too much and it will be thoroughly wasted. The first chunks of titanium are pretty good, and can reasonably be thought of as being worth 3 bucks. However, as you stack more of it the chances that you will have to sink it into a weak card just to use it up rises, as does the smaller chance that it will be wasted completely.
The punish cards in Terraforming Mars can make dabbling in lots of things a risky business. When you do that you are basically opening yourself up to every punish card out there. However, going all in on titanium or steel is a different sort of problem because you risk having a stack of resources you can't profitably use. I think in 2 player dabbling is probably best because you will get to snag half of the punish cards if you want to, and you only get through half the deck anyway so many punish cards won't even appear. Going all in on a resource just means your opponent has a huge incentive to hate draft your payoff cards, no matter what sort those might be.
I got lucky getting some of the punish cards like Hackers to steal his income, but a couple of them got passed to me. I think I dropped seven total punish cards, and all of them got full value. It doesn't seem that exciting to take a card that costs you a net 0 but takes 4 bucks from your opponent but long run that squeeze on their output is brutal. Terraforming Mars, like many games, has lots of big plays that are exciting and swingy, but it seems even more effective to take a continuous stream of small plays that are strict benefits to your situation.
So in short, you definitely need to avoid going too hard into a single resource when you can't guarantee a good use for it, and in the 2p game the punish cards are just amazing and you have to draft them highly.
One thing I found really funny is that because I had never read the rulebook I didn't know what the default game was actually like. In the base game everyone starts with one production of every resource, and in the game I was playing that rule is taken out. My impression right now is that this makes the game worse, largely because of punish cards. If everyone has a bit of everything you can actually aim your punish cards at the people you think are winning instead of just hitting the only person who happens to have the thing you are punishing. Plant strategies become more tenable because everybody is going to have some plants so meteors that blow up plants will often get aimed at people who aren't focusing hard on plants instead of always hitting the plant person.
Keeping that extra production in the game will certainly speed the game up but I have no issue with that, and I would really like to try it out and see if my thinking on punish cards works out the way I want it to.