A 2 (like all of the choices 2, 3, 5, and 6) allows for the possibility that you might be wrong. A 1 and a 7 do not - they are unskeptical, and, I don't want to be too harsh here, but I think they're dishonest.
I believe that there is only one truly skeptical number on the chart: 6 (well, maybe 5). However, I feel that 2-5 are at least somewhat skeptical. There is no evidence supporting the existence of a god, but it is possible to make the mistake of thinking there is, which is I guess one way you could arrive at a 2 or 3. A 7 makes the statement that you can prove the negative of an existential -- not only beyond a reasonable doubt, not only beyond a shadow of a doubt, but beyond
all doubt. I consider that to be an abandonment of critical thinking and skepticism. A 1 has a different problem. A 1 states that you can prove an existential, which is actually fine. The problem with a 1 is that you have no evidence supporting your position, and you haven't allowed for even the possibility that you're making a mistake with respect to what you mistakenly think is evidence.
I have heard atheists ask the rhetorical question similar to "What would be the difference between a universe with a God and one without?" I might be wording it wrong. I think this rhetorical question is an excellent argument against being a 1, 2, or 3. But if you look at it closely, I think it's an even better argument against being a 7.
I do have one caveat, though. If you are a 7 because you define God in such a way as to be a logical impossibility, that is honest. For example, if you define God as being able to create a rock so heavy he can't lift it, and also as being able to lift that rock, then you ought to be a 7. I would be a 7, defining God that way. Or, if you define God in such a way as to be a logical necessity, then you ought to be a 1 (I would call such a definition dishonest, but I think
given such a definition, it is not dishonest to be a 1).
In conclusion, Libya is a land of contrasts.