I haven't read all the posts, but looks on surface there are some excellent responses there.
Think about the sort of person you are, are you sensible, do you take lots of risks, what's you thoughts on other road users?
Think about what you need to mode of transportation for? Is it just for fun? If so, bikes are not as much fun in the rain, heavy winds, winter.
Do you want to options to carry passengers?
Have you got space for it?
I would say if you are feeling unsure, do a CBT and you will very quickly decide if this is something you want to pursue or if this is something that isn't for you. At that point you have little to lose. Bikes are covered by the training school and you will come out of it with a CBT!