Welcome!! Not sure if I can answer all these questions, but I'll try.
1. You can go ahead and apply for the AA Biz with only your name. All Chase would see is the inquiry, so it shouldn't matter.
2. This depends on what level of MSR you are comfortable with and if you want to risk taking a lower sign up bonus and ask for a match. I'm not sure about the other offers but the one with the dummy booking does give you a temporary card number to use right away. But the limit is much lower than your actual credit limit. I can't remember exactly because I did a Hilton Biz at the same time, but one of them was only $1000, when my actual credit limit was $20,000.
3. Yes, people just sign up everyone in their household for accounts, but I don't think it's that easy to get the business mailers that way. Some get them from a friend or family. Otherwise you can buy them on Reddit (but I really know nothing about that.)
4. I am only on my first, but I believe it is 95 days.
5. I would do all further business applications in your name only. Much less chance of needing documentation. Or if you do a driver's license would suffice.
6. If you can talk P2 into a CIP, there is no issue with timing. It is totally separate from your application. But maybe you'd be better off getting started with yourself and have her apply a little later. Many of us started out with reluctant P2, and it would be a shame if she had to call in or something on her first card, and decided she didn't want to do it at all.
7. Generally yes, always wait a year before canceling. Although, that may not be true for Citi AA..not sure.
I don't know if you are on Reddit, but we have a group there where there are lots of tips. Through there you can also support someone who has been helpful to you. PM
@SouthFayetteFan @Lain or
@Albort if you are interested in joining.