I am wondering if it is possible to add a check box on the Shipping option page, where the customer could add a signature required and insurance option?
I am trying to avoid to add separate shipping rates.
I don't know of any solution for adding a signature required, but there is an app called Route to offer shipping insurance. Its a free app so you can easily see if it works for what you are looking for.
There is a new app, Engarde Purchase Protection. This is a similar app to route but instead of them taking the money you make from the insurance, you get to keep all the revenue and manage the insurance process yourself. You can create your own insurance policy and then charge for it in the cart.