Just sent a response to your shinai bag question. You're making a mountain out of a mole hill. Just pull the strings toward the rest of the bag after folding it over and tie it how you like (ie knot or like how you tie your shoes).
Yeah, that's what I've gathered from the forums. It's a bit different here since there are more resources and training/grading opportunities, especially for kids.
No, it's kind of normal. The dan system in kendo is such that you can get 1-dan and 2-dan in junior high, then 3-dan in high school. Some students do just that; they start kendo in their first year, take ikkyuu then, then take 1-dan the next year, and 2-dan the year after that. The wait after ikkyuu is only six months.
Yeah, I did. I was scared shitless at the shinsa because of the written portion.