2. Most people are adequately covered by the standard 6 sizes. Ours fit particularly well - how a shirt should. It is a lot about how it fits in certain areas of the body and then drapes. We spent a ton of time perfecting our block, specific for our cotton, and then expanded it with other shirt designs. We take it a few steps further and have made a number of other sizes to fit between a Small and a Medium, and one between a Medium and a Large, and then tall sizes, tapered cuts for extremely athletic people, and a relaxed cut for heavier.
We're working on the interface now, and will have it done when the campaign ends to collect measurements. We can match you pretty well with height and weight, but chest helps a lot as well. Whatever you're comfortable giving!