I think that a first good snake really depends on the person then the species. As an example if you have a person is is really quite interestead in a Ball Python for there very first snake. If that person does the necessary research, finding out all the quirks and behaviors of a Ball Python, sets up a cage and gets everything where it supposed to be before the purchase and has done everything they way they should be doing then I see no problem with why a Ball Python, or any species of snake (excluding Hots and larger breed snakes), would make a bad first snake. I mean even something like a GTP, which is a little more advanced for keeping, would not make a bad first herp for someone as long as they knew EXACTLY what they were getting into and was willing to give the effort needed to make sure that snake had everything it needed. I don't think anyone would ever recommend a GTP as a frst snake, but if that person knows what to expect and is willing to put that effort into the care and upkeep of that snake, then I don't see it as a bad first snake, for that person.
Now on the other side of the spectrum is the impulse buyer or a person buying a herp because johnny down the street has one too. For these kind of people I 100% agree that a corn snake or something similar in ease of keeping is the snake they should be getting. At the end of the day a person like this would be more likely to be able to keep a corn alive and happy then a herp that had quite a few special needs.
1.2.1 Ball Pythons
1.0 Cali King Snake (Weebl)
0.0.1 Black Breasted Leaf Turtle (Hootie)