Schengen Visa.
I think you're going way overboard on this (booking/cancelling hotels, flights etc).
I've applied for 3 Schengen visas for my wife .... France, Spain, Netherlands.
All successfully.
We've NEVER EVER produced a travel itinery, NEVER shown bookings or confirmations of any sort, NEVER had, or been asked to show an insurance booking.
It is totally sufficient that your wife is married to a UK citizen, and that you are travelling as a couple.
