LLC/S-Corp/whatever, if you're doing this, you're going to want to make friends with a CPA, and an attorney. Everybody's needs on this front is going to be highly individualized, the couple hundred bucks spent on advice from these two professional friends are going to pay staggering dividends later.
B) Not in my experience. W2 employees have a 20% overhead for various insurances, taxes, etc. There's also significant employment law one has to follow to a T, 'or else'. Consultants, you can be a little looser with.
C) Not disagreeing on this one, but there's also _tons_ of smaller shops and startups who have expensive problems a consultant's specialized knowledge/experience may be uniquely suited to solve.
D) As a non-smoking overweight single male, my 'gold plan' insurance on the west coast is ~$400/mo. At consultant profit margins, that is effectively 'lolwhatever' money.
E) This is yet another example of why hourly billing is nuts. Don't bill hourly. Bill per-project, and charge for the business-value of the work to the business. Considerable literature has been written on this, see works by Jonathan Stark, Alan Weiss, etc. tl; dr - if you're billing hourly, you're doing it Wrong(tm)
F) Strong agree. But just because one may hate writing/speaking/meetings/selling doesn't mean one can't A. learn it, and B. learn to excel at it. Would _you_ take a course on public speaking and read a book on negotiation if you were reasonably certain you could make your current annual income in a quarter's worth of work?