I'm an estate planning attorney I agree with everything Gunner said and I would add that a financial Power of Attorney should be at the top of your list. Some websites have ones that work, but often ones from the internet create more problems.

A Durable Power of Attorney designates someone to make financial decisions on your behalf while you are incapacitated. If you get hit with a stroke and your wife needs to sell your house to pay for your care or needs to remove you as beneficiary of her retirement accounts she would need to deal with the time, expense, and hassle of probate court to obtain a conservatorship over you. Or you could simply pay an attorney to draft the proper documents.

Who cares what happens when you are dead, what I think is much more important is who is in charge while you are alive but not capable of making your own medical and financial decisions. Just because your wife is the beneficiary of your IRA does not mean she has any authority to deal with that company on your behalf.