A bit late, but there is only one way to get the best outcome: cheating.
Thanks to your limited amount of investment money, there will be failures.
The point is less that you manage to avoid them, but more to make the choices *you* think are the best.
There are a couple of situations where you are actually free to vote for or against something. Nearly all of them have benefits and drawbacks, leaving no real best choice.
So playing blind is not really that much of a drawback, you just lack the ability to prepare for certain situation less good.
You do need a walkthrough for some more ..strange playthrough, since you need to do specific actions to reach specific failures, but your goal should not be to create interesting worlds, but to try to steer Simon on his path. ^^
So, do not worry about making mistakes, since they are unavoidable.
Most walkthroughs are only efficent to follow the vision of their authors by calculating the hidden mechanics.
That does not create a better path, since the quality of the path you follow is, in my opinion, subjective.