Other things to consider. Are you going to be the main permit holder and she your dependent? Because if so you'll get a residence only permit, but it won't allow you to work being a retiree and I think it will be the same for your wife, i.e. residence only with no work rights.
If she's supposed to be the main permit holder then getting a job herself will be very difficult as Swiss/EU nationals have priority. The legal basis for the hire of non-EU nationals is given here: https://www.bfm.admin.ch/bfm/en/home...zulassung.html
I don't know how long ago you were last living here, but the US's FATCA law has had a big impact on Americans living abroad worlwide. As well as having to continue to file US tax returns you may also owe the US tax on top of your Swiss taxes. To open a basic salary/checking account here (no investment or mortgage accounts by the way) you will need to sign a W-9 form allowing your bank to send the account info on to the IRS. And if any account/s comes to more than $10,000 at any time of the year it will need to be reported on a FBAR form. http://www.irs.gov/Individuals/Inter...-Aliens-Abroad