Hi GIMA, it all sounds great! I know that would have been extremly hard for me to ask my H if he wanted to go with us, so your W gets some Brownie points! Also, the fact she is asked about adding her cell phone to the family plan...she knows you can see her calls, right? Another plus! Hope you can enjoy the trip and not worry about every little thing she says/does. You need to relax and both of you enjoy this time together.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!