Is the smoot a valid unit of measure?
It is a valid unit of measure, but since it is an unconventional one, I am not sure that it has more applicability than measuring Boston bridge lengths. And when using an unconventional unit, you should give reference to some more conventional units, like furlongs.
What is one serious, credible reason why I should consider a belief in your god(s)?
I think the only credible reason to believe in any god or supernatural is the Placebo effect. Since I am no expert in this topic and neither am I an ardent believer, I can answer this mainly from my perspective of god or life. For me any god is only equal to a feel good effect.A human mind has endless Defence mechanisms to cope with any stimuli that has a potential to harm their instant well being. These defense mechanisms generally vary from person to person.One general observation I have made about atheists are that they are extremely self confident and secure individuals. It also could be that their immense confidence in themselves have left their need to believe in a certain supernatural entity entirely redundant. Now I am not at all saying that all theists have low self confidence, but in my understanding the focal point of their confidence lies in their belief in their god.Now coming back to defence mechanisms, a theist may resort to his god to keep himself calm during a massive mid air turbulence whereas an atheist I suspect would bank on his confidence in his irrefutable rationale. Now if the end result of being calm is achieved by either of the ways, I don't think it would matter which way you chose.So my point is that if you feel you can create a structured way of thinking logically when facing challenges or adverse situations in life, there is no need to believe in any god. And if you are lazy like I am, you can burn a few incense sticks and read Hanuman Chalisa before going to give an engineering examination with minimum preparation and feel confident enough to at least sit for the examination.