to answer question 1, honestly neither. roll a 14 or 15 pot for the BO and class your elite as a planesman and sell it. the whole should i use a seaman on a BB is a harder question to answer, most dont use seaman on BB.

Personally, I think the BB and CV starter packs are worthless. They don't give you the proper amount of crew you need and it would be better to spend your money on other stuff.

1.) However, it is too late now so... I would class your potential sailor as a Planesman and use it on one of your subs or sell it. Seaman isn't really necessary on a BB because there are other sailors such as the Engineer or Repairer that are more efficient and useful.

2.) These dots aren't directly related to your angles. They are able to be used more for mental range markers. Such as angle 20 is (x) dots from the end of my guidelines.

Most people use about 5 engineers and 3 or 4 repairers. AA is only useful if you are good at being able to multi-task and shoot enemies and AA at the same time. Some nations almost require 2 sets of gunners though. Usually personal preference and you can ask other players what their though on it is.

Hope this helps,
Vette117