Hired Supers have higher pay scales which include a benefit package, career development and/or other perks. Canceling a contract could result in severance and leave pay. Additional costs could include fees for search and hiring. Paying out severance/leave packages could be very costly in addition to paying another hired Super.
Some of what you say is true. Other things are true, but overdramatize the issue. True: On average appointed supers make more. Also true: On average they also have more administrative experience and better credentials than elected. True: a super might ask for career development money in his/her contract. Also true: career development is continuing education. I think I am okay with someone in a leadership role asking for career development/training. True: There could be a severance package cost if the contract is terminated at the board's pleasure. Also true: Most contracts have non-performance clauses that vitiate payouts based upon certain actions. This seems a better alternative than waiting 4 years until the next election, or waiting on a governor to fire a super. True: When a super leaves, you may have to pay for accrued leave. Also true: Elected or appointed, leave is currently accrued. Also true: Easily solved the way many companies do it, put in a Use it or lose it policy. Also true, to get a clean audit, the school system already accrues for the cost of leave that would have to be paid out. This is standard accounting. Nothing earth shattering. True: the super would have a benefits package. Also true: school system employees already have good benefits that cost the system.
True: recruitment will cost money. Also true: recruitment is currently known as campaign contributions. Usually from cronies who want the school district to buy their land, etc.
It seems to me that every concern that is brought up by the NO vote are really easy issues that businesses address every day. A board with experienced business professionals could handle all of these things.
True: recruitment is a potential cost that would be bore by the school system. Also true: Recruitment is currently bring paid for by a few cronies who call it campaign contributions.